20818725 has 24 divisors (see below), whose sum is σ = 34685280. Its totient is φ = 11017920.

The previous prime is 20818649. The next prime is 20818739. The reversal of 20818725 is 52781802.

It is not a de Polignac number, because 20818725 - 2⁷ = 20818597 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9427 + ... + 11423.

It is an arithmetic number, because the mean of its divisors is an integer number (1445220).

Almost surely, 2^20818725 is an apocalyptic number.

20818725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20818725 is a deficient number, since it is larger than the sum of its proper divisors (13866555).

20818725 is a wasteful number, since it uses less digits than its factorization.

20818725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2149 (or 2144 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 33.

The square root of 20818725 is about 4562.7541025131. The cubic root of 20818725 is about 275.0962748311.

The spelling of 20818725 in words is "twenty million, eight hundred eighteen thousand, seven hundred twenty-five".