1285273440 has 768 divisors, whose sum is σ = 5460618240. Its totient is φ = 278691840.

The previous prime is 1285273439. The next prime is 1285273441. The reversal of 1285273440 is 443725821.

It is a happy number.

1285273440 is a `hidden beast` number, since 128 + 527 + 3 + 4 + 4 + 0 = 666.

1285273440 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (1285273439) and next prime (1285273441).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1285273395 and 1285273404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1285273441) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 29890059 + ... + 29890101.

It is an arithmetic number, because the mean of its divisors is an integer number (7110180).

Almost surely, 2^1285273440 is an apocalyptic number.

1285273440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1285273440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2730309120).

1285273440 is an abundant number, since it is smaller than the sum of its proper divisors (4175344800).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1285273440 is a wasteful number, since it uses less digits than its factorization.

1285273440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132 (or 118 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 36.

The square root of 1285273440 is about 35850.7104532114. The cubic root of 1285273440 is about 1087.2560784683.

The spelling of 1285273440 in words is "one billion, two hundred eighty-five million, two hundred seventy-three thousand, four hundred forty".