64881660 has 24 divisors (see below), whose sum is σ = 181668816. Its totient is φ = 17301760.

The previous prime is 64881659. The next prime is 64881679. The reversal of 64881660 is 6618846.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 540621 + ... + 540740.

It is an arithmetic number, because the mean of its divisors is an integer number (7569534).

Almost surely, 2^64881660 is an apocalyptic number.

64881660 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

64881660 is an abundant number, since it is smaller than the sum of its proper divisors (116787156).

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

64881660 is a wasteful number, since it uses less digits than its factorization.

64881660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1081373 (or 1081371 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 39.

The square root of 64881660 is about 8054.9152695730. The cubic root of 64881660 is about 401.8284211225.

The spelling of 64881660 in words is "sixty-four million, eight hundred eighty-one thousand, six hundred sixty".