20891925 has 72 divisors (see below), whose sum is σ = 41073760. Its totient is φ = 10497600.

The previous prime is 20891891. The next prime is 20891933. The reversal of 20891925 is 52919802.

It is not a de Polignac number, because 20891925 - 2⁸ = 20891669 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20891925.

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 in 71 ways as a sum of consecutive naturals, for example, 115335 + ... + 115515.

Almost surely, 2^20891925 is an apocalyptic number.

20891925 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20891925 is a deficient number, since it is larger than the sum of its proper divisors (20181835).

20891925 is a wasteful number, since it uses less digits than its factorization.

20891925 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 225 (or 208 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 20891925 is about 4570.7685349403. The cubic root of 20891925 is about 275.4183165228.

The spelling of 20891925 in words is "twenty million, eight hundred ninety-one thousand, nine hundred twenty-five".