64520428 has 48 divisors (see below), whose sum is σ = 141765120. Its totient is φ = 25052544.

The previous prime is 64520419. The next prime is 64520431. The reversal of 64520428 is 82402546.

It is a self number, because there is not a number n which added to its sum of digits gives 64520428.

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, 9600 + ... + 14872.

It is an arithmetic number, because the mean of its divisors is an integer number (2953440).

Almost surely, 2^64520428 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 64520428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (70882560).

64520428 is an abundant number, since it is smaller than the sum of its proper divisors (77244692).

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

64520428 is a wasteful number, since it uses less digits than its factorization.

64520428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5326 (or 5324 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 31.

The square root of 64520428 is about 8032.4608931510. The cubic root of 64520428 is about 401.0812993454.

The spelling of 64520428 in words is "sixty-four million, five hundred twenty thousand, four hundred twenty-eight".