20953825 has 6 divisors (see below), whose sum is σ = 25982774. Its totient is φ = 16763040.

The previous prime is 20953819. The next prime is 20953831. The reversal of 20953825 is 52835902.

It is an interprime number because it is at equal distance from previous prime (20953819) and next prime (20953831).

It can be written as a sum of positive squares in 3 ways, for example, as 5089536 + 15864289 = 2256^2 + 3983^2 .

It is not a de Polignac number, because 20953825 - 2⁹ = 20953313 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 419052 + ... + 419101.

Almost surely, 2^20953825 is an apocalyptic number.

20953825 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20953825 is a deficient number, since it is larger than the sum of its proper divisors (5028949).

20953825 is an equidigital number, since it uses as much as digits as its factorization.

20953825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 838163 (or 838158 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 34.

The square root of 20953825 is about 4577.5348169075. The cubic root of 20953825 is about 275.6900576234.

The spelling of 20953825 in words is "twenty million, nine hundred fifty-three thousand, eight hundred twenty-five".