21064466 has 4 divisors (see below), whose sum is σ = 31596702. Its totient is φ = 10532232.

The previous prime is 21064363. The next prime is 21064471. The reversal of 21064466 is 66446012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 17397241 + 3667225 = 4171^2 + 1915^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5266115 + ... + 5266118.

Almost surely, 2^21064466 is an apocalyptic number.

21064466 is a deficient number, since it is larger than the sum of its proper divisors (10532236).

21064466 is a wasteful number, since it uses less digits than its factorization.

21064466 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10532235.

The product of its (nonzero) digits is 6912, while the sum is 29.

The square root of 21064466 is about 4589.6041223618. The cubic root of 21064466 is about 276.1744416384.

The spelling of 21064466 in words is "twenty-one million, sixty-four thousand, four hundred sixty-six".