64008921 has 4 divisors (see below), whose sum is σ = 85345232. Its totient is φ = 42672612.

The previous prime is 64008911. The next prime is 64008941. The reversal of 64008921 is 12980046.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a de Polignac number, because none of the positive numbers 2^k-64008921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64008911) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10668151 + ... + 10668156.

It is an arithmetic number, because the mean of its divisors is an integer number (21336308).

Almost surely, 2^64008921 is an apocalyptic number.

It is an amenable number.

64008921 is a deficient number, since it is larger than the sum of its proper divisors (21336311).

64008921 is a wasteful number, since it uses less digits than its factorization.

64008921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21336310.

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 64008921 is about 8000.5575430716. The cubic root of 64008921 is about 400.0185845532.

Adding to 64008921 its reverse (12980046), we get a palindrome (76988967).

The spelling of 64008921 in words is "sixty-four million, eight thousand, nine hundred twenty-one".