64691520 has 112 divisors (see below), whose sum is σ = 208239360. Its totient is φ = 17012736.

The previous prime is 64691507. The next prime is 64691521. The reversal of 64691520 is 2519646.

64691520 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64691521) by changing a digit.

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, 75414 + ... + 76266.

It is an arithmetic number, because the mean of its divisors is an integer number (1859280).

Almost surely, 2^64691520 is an apocalyptic number.

64691520 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 64691520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104119680).

64691520 is an abundant number, since it is smaller than the sum of its proper divisors (143547840).

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

64691520 is a wasteful number, since it uses less digits than its factorization.

64691520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 952 (or 942 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 33.

The square root of 64691520 is about 8043.1038784788. The cubic root of 64691520 is about 401.4355087902.

The spelling of 64691520 in words is "sixty-four million, six hundred ninety-one thousand, five hundred twenty".