64618440 has 32 divisors (see below), whose sum is σ = 193855680. Its totient is φ = 17231552.

The previous prime is 64618439. The next prime is 64618451. The reversal of 64618440 is 4481646.

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, 269124 + ... + 269363.

It is an arithmetic number, because the mean of its divisors is an integer number (6057990).

Almost surely, 2^64618440 is an apocalyptic number.

64618440 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

64618440 is an abundant number, since it is smaller than the sum of its proper divisors (129237240).

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

64618440 is a wasteful number, since it uses less digits than its factorization.

64618440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 538501 (or 538497 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 33.

The square root of 64618440 is about 8038.5595724607. The cubic root of 64618440 is about 401.2842887595.

The spelling of 64618440 in words is "sixty-four million, six hundred eighteen thousand, four hundred forty".