1265145440 has 192 divisors, whose sum is σ = 3503896704. Its totient is φ = 427327488.

The previous prime is 1265145397. The next prime is 1265145463. The reversal of 1265145440 is 445415621.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 1265145397 and 1265145406.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1307837 + ... + 1308803.

It is an arithmetic number, because the mean of its divisors is an integer number (18249462).

Almost surely, 2^1265145440 is an apocalyptic number.

1265145440 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 1265145440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1751948352).

1265145440 is an abundant number, since it is smaller than the sum of its proper divisors (2238751264).

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

1265145440 is a wasteful number, since it uses less digits than its factorization.

1265145440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1049 (or 1041 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 32.

The square root of 1265145440 is about 35568.8830299744. The cubic root of 1265145440 is about 1081.5505391963.

The spelling of 1265145440 in words is "one billion, two hundred sixty-five million, one hundred forty-five thousand, four hundred forty".