64720320 has 112 divisors (see below), whose sum is σ = 234866688. Its totient is φ = 14791680.

The previous prime is 64720303. The next prime is 64720339. The reversal of 64720320 is 2302746.

It is a tau number, because it is divible by the number of its divisors (112).

It is a Harshad number since it is a multiple of its sum of digits (24).

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, 1905 + ... + 11535.

It is an arithmetic number, because the mean of its divisors is an integer number (2097024).

Almost surely, 2^64720320 is an apocalyptic number.

64720320 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64720320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117433344).

64720320 is an abundant number, since it is smaller than the sum of its proper divisors (170146368).

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

64720320 is a wasteful number, since it uses less digits than its factorization.

64720320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9658 (or 9648 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 24.

The square root of 64720320 is about 8044.8940328633. The cubic root of 64720320 is about 401.4950716067.

The spelling of 64720320 in words is "sixty-four million, seven hundred twenty thousand, three hundred twenty".