1275249420 has 144 divisors (see below), whose sum is σ = 4031078688. Its totient is φ = 338411520.

The previous prime is 1275249419. The next prime is 1275249427. The reversal of 1275249420 is 249425721.

1275249420 is a `hidden beast` number, since 1 + 27 + 524 + 94 + 20 = 666.

It is a super-2 number, since 2×1275249420² = 3252522166420672800, which contains 22 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (1275249427) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1248510 + ... + 1249530.

It is an arithmetic number, because the mean of its divisors is an integer number (27993602).

Almost surely, 2^1275249420 is an apocalyptic number.

1275249420 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 1275249420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2015539344).

1275249420 is an abundant number, since it is smaller than the sum of its proper divisors (2755829268).

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

1275249420 is a wasteful number, since it uses less digits than its factorization.

1275249420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1302 (or 1288 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The square root of 1275249420 is about 35710.6345505089. The cubic root of 1275249420 is about 1084.4221462336.

The spelling of 1275249420 in words is "one billion, two hundred seventy-five million, two hundred forty-nine thousand, four hundred twenty".