20842564 has 12 divisors (see below), whose sum is σ = 36506988. Its totient is φ = 10412000.

The previous prime is 20842553. The next prime is 20842579. The reversal of 20842564 is 46524802.

It can be written as a sum of positive squares in 2 ways, for example, as 3686400 + 17156164 = 1920^2 + 4142^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6234 + ... + 8974.

It is an arithmetic number, because the mean of its divisors is an integer number (3042249).

Almost surely, 2^20842564 is an apocalyptic number.

It is an amenable number.

20842564 is a deficient number, since it is larger than the sum of its proper divisors (15664424).

20842564 is a wasteful number, since it uses less digits than its factorization.

20842564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4646 (or 4644 counting only the distinct ones).

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

The square root of 20842564 is about 4565.3657027669. The cubic root of 20842564 is about 275.2012367271.

The spelling of 20842564 in words is "twenty million, eight hundred forty-two thousand, five hundred sixty-four".