20977925 has 6 divisors (see below), whose sum is σ = 26012658. Its totient is φ = 16782320.

The previous prime is 20977889. The next prime is 20977951. The reversal of 20977925 is 52977902.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 6240004 + 14737921 = 2498^2 + 3839^2 .

It is not a de Polignac number, because 20977925 - 2⁶ = 20977861 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 419534 + ... + 419583.

It is an arithmetic number, because the mean of its divisors is an integer number (4335443).

Almost surely, 2^20977925 is an apocalyptic number.

20977925 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20977925 is a deficient number, since it is larger than the sum of its proper divisors (5034733).

20977925 is an equidigital number, since it uses as much as digits as its factorization.

20977925 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 839127 (or 839122 counting only the distinct ones).

The product of its (nonzero) digits is 79380, while the sum is 41.

The square root of 20977925 is about 4580.1664816904. The cubic root of 20977925 is about 275.7957119175.

The spelling of 20977925 in words is "twenty million, nine hundred seventy-seven thousand, nine hundred twenty-five".