64613920 has 96 divisors (see below), whose sum is σ = 180182016. Its totient is φ = 21427200.

The previous prime is 64613881. The next prime is 64613921. The reversal of 64613920 is 2931646.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is not an unprimeable number, because it can be changed into a prime (64613921) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33790 + ... + 35650.

It is an arithmetic number, because the mean of its divisors is an integer number (1876896).

Almost surely, 2^64613920 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 64613920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90091008).

64613920 is an abundant number, since it is smaller than the sum of its proper divisors (115568096).

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

64613920 is a wasteful number, since it uses less digits than its factorization.

64613920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1914 (or 1906 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 31.

The square root of 64613920 is about 8038.2784226475. The cubic root of 64613920 is about 401.2749320533.

The spelling of 64613920 in words is "sixty-four million, six hundred thirteen thousand, nine hundred twenty".