64157720 has 64 divisors (see below), whose sum is σ = 161187840. Its totient is φ = 22780800.

The previous prime is 64157713. The next prime is 64157747. The reversal of 64157720 is 2775146.

64157720 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17225 + ... + 20615.

It is an arithmetic number, because the mean of its divisors is an integer number (2518560).

Almost surely, 2^64157720 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 64157720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80593920).

64157720 is an abundant number, since it is smaller than the sum of its proper divisors (97030120).

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

64157720 is a wasteful number, since it uses less digits than its factorization.

64157720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3456 (or 3452 counting only the distinct ones).

The product of its (nonzero) digits is 11760, while the sum is 32.

The square root of 64157720 is about 8009.8514343276. The cubic root of 64157720 is about 400.3283137848.

The spelling of 64157720 in words is "sixty-four million, one hundred fifty-seven thousand, seven hundred twenty".