21050025 has 24 divisors (see below), whose sum is σ = 34935264. Its totient is φ = 11184000.

The previous prime is 21050017. The next prime is 21050033. The reversal of 21050025 is 52005012.

It is an interprime number because it is at equal distance from previous prime (21050017) and next prime (21050033).

It is not a de Polignac number, because 21050025 - 2³ = 21050017 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a junction number, because it is equal to n+sod(n) for n = 21049986 and 21050013.

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, 34725 + ... + 35325.

It is an arithmetic number, because the mean of its divisors is an integer number (1455636).

Almost surely, 2^21050025 is an apocalyptic number.

21050025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21050025 is a deficient number, since it is larger than the sum of its proper divisors (13885239).

21050025 is a wasteful number, since it uses less digits than its factorization.

21050025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1081 (or 1076 counting only the distinct ones).

The product of its (nonzero) digits is 100, while the sum is 15.

The square root of 21050025 is about 4588.0306232631. The cubic root of 21050025 is about 276.1113156319. Note that the first 3 decimals are identical.

Adding to 21050025 its reverse (52005012), we get a palindrome (73055037).

The spelling of 21050025 in words is "twenty-one million, fifty thousand, twenty-five".