20564266 has 4 divisors (see below), whose sum is σ = 30846402. Its totient is φ = 10282132.

The previous prime is 20564209. The next prime is 20564279. The reversal of 20564266 is 66246502.

20564266 is nontrivially palindromic in base 14.

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., 17048641 + 3515625 = 4129^2 + 1875^2 .

It is a super-2 number, since 2×20564266² = 845778072237512, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5141065 + ... + 5141068.

Almost surely, 2^20564266 is an apocalyptic number.

20564266 is a deficient number, since it is larger than the sum of its proper divisors (10282136).

20564266 is a wasteful number, since it uses less digits than its factorization.

20564266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10282135.

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 20564266 is about 4534.7840080868. The cubic root of 20564266 is about 273.9708797440.

The spelling of 20564266 in words is "twenty million, five hundred sixty-four thousand, two hundred sixty-six".