20406625 has 16 divisors (see below), whose sum is σ = 25908480. Its totient is φ = 16042800.

The previous prime is 20406611. The next prime is 20406641. The reversal of 20406625 is 52660402.

It is not a de Polignac number, because 20406625 - 2¹¹ = 20404577 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a self number, because there is not a number n which added to its sum of digits gives 20406625.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5992 + ... + 8758.

It is an arithmetic number, because the mean of its divisors is an integer number (1619280).

Almost surely, 2^20406625 is an apocalyptic number.

20406625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20406625 is a deficient number, since it is larger than the sum of its proper divisors (5501855).

20406625 is an equidigital number, since it uses as much as digits as its factorization.

20406625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2841 (or 2831 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 25.

The square root of 20406625 is about 4517.3692565474. The cubic root of 20406625 is about 273.2690170241.

The spelling of 20406625 in words is "twenty million, four hundred six thousand, six hundred twenty-five".