20156725 has 6 divisors (see below), whose sum is σ = 24994370. Its totient is φ = 16125360.

The previous prime is 20156693. The next prime is 20156729. The reversal of 20156725 is 52765102.

It can be written as a sum of positive squares in 3 ways, for example, as 148996 + 20007729 = 386^2 + 4473^2 .

It is not a de Polignac number, because 20156725 - 2⁵ = 20156693 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20156693 and 20156702.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20156729) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 403110 + ... + 403159.

Almost surely, 2^20156725 is an apocalyptic number.

20156725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20156725 is a deficient number, since it is larger than the sum of its proper divisors (4837645).

20156725 is an equidigital number, since it uses as much as digits as its factorization.

20156725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 806279 (or 806274 counting only the distinct ones).

The product of its (nonzero) digits is 4200, while the sum is 28.

The square root of 20156725 is about 4489.6241490797. The cubic root of 20156725 is about 272.1489461405.

The spelling of 20156725 in words is "twenty million, one hundred fifty-six thousand, seven hundred twenty-five".