20925745 has 32 divisors (see below), whose sum is σ = 28212480. Its totient is φ = 14826240.

The previous prime is 20925743. The next prime is 20925761. The reversal of 20925745 is 54752902.

It is not a de Polignac number, because 20925745 - 2¹ = 20925743 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20925745.

It is not an unprimeable number, because it can be changed into a prime (20925743) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 133207 + ... + 133363.

It is an arithmetic number, because the mean of its divisors is an integer number (881640).

Almost surely, 2^20925745 is an apocalyptic number.

It is an amenable number.

20925745 is a deficient number, since it is larger than the sum of its proper divisors (7286735).

20925745 is a wasteful number, since it uses less digits than its factorization.

20925745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 265.

The product of its (nonzero) digits is 25200, while the sum is 34.

The square root of 20925745 is about 4574.4666355762. The cubic root of 20925745 is about 275.5668527918.

The spelling of 20925745 in words is "twenty million, nine hundred twenty-five thousand, seven hundred forty-five".