20616556 has 24 divisors (see below), whose sum is σ = 37830240. Its totient is φ = 9812352.

The previous prime is 20616521. The next prime is 20616559. The reversal of 20616556 is 65561602.

It is a super-2 number, since 2×20616556² = 850084762602272, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20616559) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25080 + ... + 25888.

It is an arithmetic number, because the mean of its divisors is an integer number (1576260).

Almost surely, 2^20616556 is an apocalyptic number.

It is an amenable number.

20616556 is a deficient number, since it is larger than the sum of its proper divisors (17213684).

20616556 is a wasteful number, since it uses less digits than its factorization.

20616556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1113 (or 1111 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 31.

The square root of 20616556 is about 4540.5457821720. The cubic root of 20616556 is about 274.2028972957.

The spelling of 20616556 in words is "twenty million, six hundred sixteen thousand, five hundred fifty-six".