64940644860 has 192 divisors, whose sum is σ = 223928312832. Its totient is φ = 13693630464.

The previous prime is 64940644859. The next prime is 64940644889. The reversal of 64940644860 is 6844604946.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 15160279 + ... + 15164561.

It is an arithmetic number, because the mean of its divisors is an integer number (1166293296).

Almost surely, 2^64940644860 is an apocalyptic number.

64940644860 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 64940644860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (111964156416).

64940644860 is an abundant number, since it is smaller than the sum of its proper divisors (158987667972).

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

64940644860 is a wasteful number, since it uses less digits than its factorization.

64940644860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7092 (or 7090 counting only the distinct ones).

The product of its (nonzero) digits is 3981312, while the sum is 51.

The spelling of 64940644860 in words is "sixty-four billion, nine hundred forty million, six hundred forty-four thousand, eight hundred sixty".