64977920 has 176 divisors, whose sum is σ = 186686400. Its totient is φ = 21676032.

The previous prime is 64977919. The next prime is 64977931. The reversal of 64977920 is 2977946.

It is a congruent number.

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, 1756142 + ... + 1756178.

Almost surely, 2^64977920 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64977920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93343200).

64977920 is an abundant number, since it is smaller than the sum of its proper divisors (121708480).

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

64977920 is an equidigital number, since it uses as much as digits as its factorization.

64977920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83 (or 51 counting only the distinct ones).

The product of its (nonzero) digits is 190512, while the sum is 44.

The square root of 64977920 is about 8060.8882885201. Note that the first 3 decimals coincide. The cubic root of 64977920 is about 402.0270437158.

The spelling of 64977920 in words is "sixty-four million, nine hundred seventy-seven thousand, nine hundred twenty".