65696257440 has 384 divisors, whose sum is σ = 264046003200. Its totient is φ = 15087928320.

The previous prime is 65696257411. The next prime is 65696257489. The reversal of 65696257440 is 4475269656.

65696257440 is a `hidden beast` number, since 6 + 5 + 6 + 9 + 62 + 574 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 866499 + ... + 939261.

It is an arithmetic number, because the mean of its divisors is an integer number (687619800).

Almost surely, 2^65696257440 is an apocalyptic number.

65696257440 is a gapful number since it is divisible by the number (60) 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 65696257440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (132023001600).

65696257440 is an abundant number, since it is smaller than the sum of its proper divisors (198349745760).

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

65696257440 is a wasteful number, since it uses less digits than its factorization.

65696257440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72817 (or 72803 counting only the distinct ones).

The product of its (nonzero) digits is 10886400, while the sum is 54.

The spelling of 65696257440 in words is "sixty-five billion, six hundred ninety-six million, two hundred fifty-seven thousand, four hundred forty".