64931818 has 32 divisors (see below), whose sum is σ = 115524864. Its totient is φ = 26790912.

The previous prime is 64931809. The next prime is 64931827. The reversal of 64931818 is 81813946.

It is an interprime number because it is at equal distance from previous prime (64931809) and next prime (64931827).

It is a super-2 number, since 2×64931818² = 8432281977570248, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 52746 + ... + 53962.

It is an arithmetic number, because the mean of its divisors is an integer number (3610152).

Almost surely, 2^64931818 is an apocalyptic number.

64931818 is a deficient number, since it is larger than the sum of its proper divisors (50593046).

64931818 is a wasteful number, since it uses less digits than its factorization.

64931818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1366.

The product of its digits is 41472, while the sum is 40.

The square root of 64931818 is about 8058.0281707127. The cubic root of 64931818 is about 401.9319414828.

The spelling of 64931818 in words is "sixty-four million, nine hundred thirty-one thousand, eight hundred eighteen".