64640860 has 12 divisors (see below), whose sum is σ = 135745848. Its totient is φ = 25856336.

The previous prime is 64640827. The next prime is 64640861. The reversal of 64640860 is 6804646.

It is a super-3 number, since 3×64640860³ (a number of 24 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64640861) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1616002 + ... + 1616041.

It is an arithmetic number, because the mean of its divisors is an integer number (11312154).

Almost surely, 2^64640860 is an apocalyptic number.

It is an amenable number.

64640860 is an abundant number, since it is smaller than the sum of its proper divisors (71104988).

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

64640860 is a wasteful number, since it uses less digits than its factorization.

64640860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3232052 (or 3232050 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 34.

The square root of 64640860 is about 8039.9539799678. The cubic root of 64640860 is about 401.3306932298.

The spelling of 64640860 in words is "sixty-four million, six hundred forty thousand, eight hundred sixty".