20863156 has 6 divisors (see below), whose sum is σ = 36510530. Its totient is φ = 10431576.

The previous prime is 20863147. The next prime is 20863169. The reversal of 20863156 is 65136802.

It can be written as a sum of positive squares in only one way, i.e., 20106256 + 756900 = 4484^2 + 870^2 .

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 2607891 + ... + 2607898.

Almost surely, 2^20863156 is an apocalyptic number.

It is an amenable number.

20863156 is a deficient number, since it is larger than the sum of its proper divisors (15647374).

20863156 is a wasteful number, since it uses less digits than its factorization.

20863156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5215793 (or 5215791 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 20863156 is about 4567.6203870287. The cubic root of 20863156 is about 275.2918378422.

Adding to 20863156 its reverse (65136802), we get a palindrome (85999958).

The spelling of 20863156 in words is "twenty million, eight hundred sixty-three thousand, one hundred fifty-six".