20657025 has 45 divisors (see below), whose sum is σ = 38646553. Its totient is φ = 10908000.

The previous prime is 20656991. The next prime is 20657027. The reversal of 20657025 is 52075602.

20657025 = T₁₂₇₃ + T₁₂₇₄ + ... + T₁₂₉₇.

The square root of 20657025 is 4545.

It is a perfect power (a square), and thus also a powerful number.

20657025 is a `hidden beast` number, since 2 + 0 + 657 + 0 + 2 + 5 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 3814209 + 16842816 = 1953^2 + 4104^2 .

It is a tau number, because it is divible by the number of its divisors (45).

It is not a de Polignac number, because 20657025 - 2¹⁵ = 20624257 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20657025.

It is not an unprimeable number, because it can be changed into a prime (20657027) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 204475 + ... + 204575.

Almost surely, 2^20657025 is an apocalyptic number.

20657025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20657025 is the 4545-th square number.

20657025 is the 2273-rd centered octagonal number.

It is an amenable number.

20657025 is a deficient number, since it is larger than the sum of its proper divisors (17989528).

20657025 is an equidigital number, since it uses as much as digits as its factorization.

20657025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 224 (or 109 counting only the distinct ones).

The product of its (nonzero) digits is 4200, while the sum is 27.

The cubic root of 20657025 is about 274.3821943655.

The spelling of 20657025 in words is "twenty million, six hundred fifty-seven thousand, twenty-five".