6440657532 has 12 divisors (see below), whose sum is σ = 15028200936. Its totient is φ = 2146885840.

The previous prime is 6440657491. The next prime is 6440657567. The reversal of 6440657532 is 2357560446.

It is a tau number, because it is divible by the number of its divisors (12).

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 268360719 + ... + 268360742.

It is an arithmetic number, because the mean of its divisors is an integer number (1252350078).

Almost surely, 2^6440657532 is an apocalyptic number.

It is an amenable number.

6440657532 is an abundant number, since it is smaller than the sum of its proper divisors (8587543404).

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

6440657532 is a wasteful number, since it uses less digits than its factorization.

6440657532 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 536721468 (or 536721466 counting only the distinct ones).

The product of its (nonzero) digits is 604800, while the sum is 42.

The square root of 6440657532 is about 80253.7072788541. The cubic root of 6440657532 is about 1860.5588111689.

The spelling of 6440657532 in words is "six billion, four hundred forty million, six hundred fifty-seven thousand, five hundred thirty-two".