21356025 has 12 divisors (see below), whose sum is σ = 35308752. Its totient is φ = 11389840.

The previous prime is 21356003. The next prime is 21356047. The reversal of 21356025 is 52065312.

It is an interprime number because it is at equal distance from previous prime (21356003) and next prime (21356047).

It is not a de Polignac number, because 21356025 - 2⁷ = 21355897 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21355986 and 21356004.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 142299 + ... + 142448.

It is an arithmetic number, because the mean of its divisors is an integer number (2942396).

Almost surely, 2^21356025 is an apocalyptic number.

21356025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21356025 is a deficient number, since it is larger than the sum of its proper divisors (13952727).

21356025 is a wasteful number, since it uses less digits than its factorization.

21356025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284760 (or 284755 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 24.

The square root of 21356025 is about 4621.2579456248. The cubic root of 21356025 is about 277.4428094139.

The spelling of 21356025 in words is "twenty-one million, three hundred fifty-six thousand, twenty-five".