20977131 has 16 divisors (see below), whose sum is σ = 32029184. Its totient is φ = 11962944.

The previous prime is 20977129. The next prime is 20977139. The reversal of 20977131 is 13177902.

It is not a de Polignac number, because 20977131 - 2¹ = 20977129 is a prime.

It is a super-2 number, since 2×20977131² = 880080049982322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20977139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19791 + ... + 20823.

It is an arithmetic number, because the mean of its divisors is an integer number (2001824).

Almost surely, 2^20977131 is an apocalyptic number.

20977131 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

20977131 is a deficient number, since it is larger than the sum of its proper divisors (11052053).

20977131 is a wasteful number, since it uses less digits than its factorization.

20977131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2010.

The product of its (nonzero) digits is 2646, while the sum is 30.

The square root of 20977131 is about 4580.0798027982. The cubic root of 20977131 is about 275.7922323144.

The spelling of 20977131 in words is "twenty million, nine hundred seventy-seven thousand, one hundred thirty-one".