64421525 has 36 divisors (see below), whose sum is σ = 95163552. Its totient is φ = 43112160.

The previous prime is 64421509. The next prime is 64421549. The reversal of 64421525 is 52512446.

It is not a de Polignac number, because 64421525 - 2⁴ = 64421509 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 52064 + ... + 53286.

It is an arithmetic number, because the mean of its divisors is an integer number (2643432).

Almost surely, 2^64421525 is an apocalyptic number.

It is an amenable number.

64421525 is a deficient number, since it is larger than the sum of its proper divisors (30742027).

64421525 is a wasteful number, since it uses less digits than its factorization.

64421525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1290 (or 1278 counting only the distinct ones).

The product of its digits is 9600, while the sum is 29.

The square root of 64421525 is about 8026.3020750530. The cubic root of 64421525 is about 400.8762561197.

It can be divided in two parts, 64421 and 525, that added together give a palindrome (64946).

The spelling of 64421525 in words is "sixty-four million, four hundred twenty-one thousand, five hundred twenty-five".