6402664251 has 64 divisors (see below), whose sum is σ = 10232640000. Its totient is φ = 3944578176.

The previous prime is 6402664231. The next prime is 6402664319. The reversal of 6402664251 is 1524662046.

6402664251 is a `hidden beast` number, since 6 + 4 + 0 + 2 + 6 + 642 + 5 + 1 = 666.

It is not a de Polignac number, because 6402664251 - 2⁹ = 6402663739 is a prime.

It is a super-2 number, since 2×6402664251² = 81988219022066782002, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (6402664201) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3745585 + ... + 3747293.

It is an arithmetic number, because the mean of its divisors is an integer number (159885000).

Almost surely, 2^6402664251 is an apocalyptic number.

6402664251 is a deficient number, since it is larger than the sum of its proper divisors (3829975749).

6402664251 is a wasteful number, since it uses less digits than its factorization.

6402664251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1913 (or 1907 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The square root of 6402664251 is about 80016.6498361435. The cubic root of 6402664251 is about 1856.8931301554.

The spelling of 6402664251 in words is "six billion, four hundred two million, six hundred sixty-four thousand, two hundred fifty-one".