21274625 has 8 divisors (see below), whose sum is σ = 26550888. Its totient is φ = 17019600.

The previous prime is 21274619. The next prime is 21274639. The reversal of 21274625 is 52647212.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 50176 + 21224449 = 224^2 + 4607^2 .

It is not a de Polignac number, because 21274625 - 2¹⁰ = 21273601 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 84974 + ... + 85223.

It is an arithmetic number, because the mean of its divisors is an integer number (3318861).

It is a Proth number, since it is equal to 2597 ⋅ 2¹³ + 1 and 2597 < 2¹³.

Almost surely, 2^21274625 is an apocalyptic number.

21274625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21274625 is a deficient number, since it is larger than the sum of its proper divisors (5276263).

21274625 is an equidigital number, since it uses as much as digits as its factorization.

21274625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170212 (or 170202 counting only the distinct ones).

The product of its digits is 6720, while the sum is 29.

The square root of 21274625 is about 4612.4424115646. The cubic root of 21274625 is about 277.0898629751.

The spelling of 21274625 in words is "twenty-one million, two hundred seventy-four thousand, six hundred twenty-five".