64777988 has 24 divisors (see below), whose sum is σ = 125768160. Its totient is φ = 28944320.

The previous prime is 64777987. The next prime is 64777997. The reversal of 64777988 is 88977746.

It is not an unprimeable number, because it can be changed into a prime (64777981) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9881 + ... + 15072.

It is an arithmetic number, because the mean of its divisors is an integer number (5240340).

Almost surely, 2^64777988 is an apocalyptic number.

It is an amenable number.

64777988 is a deficient number, since it is larger than the sum of its proper divisors (60990172).

64777988 is a wasteful number, since it uses less digits than its factorization.

64777988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25027 (or 25025 counting only the distinct ones).

The product of its digits is 4741632, while the sum is 56.

The square root of 64777988 is about 8048.4773715281. The cubic root of 64777988 is about 401.6142847810.

The spelling of 64777988 in words is "sixty-four million, seven hundred seventy-seven thousand, nine hundred eighty-eight".