21122025 has 12 divisors (see below), whose sum is σ = 34921872. Its totient is φ = 11265040.

The previous prime is 21122009. The next prime is 21122033. The reversal of 21122025 is 52022112.

It is not a de Polignac number, because 21122025 - 2⁴ = 21122009 is a prime.

It is a super-2 number, since 2×21122025² = 892279880201250, which contains 22 as substring.

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 = 21121995 and 21122013.

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, 140739 + ... + 140888.

It is an arithmetic number, because the mean of its divisors is an integer number (2910156).

Almost surely, 2^21122025 is an apocalyptic number.

21122025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21122025 is a deficient number, since it is larger than the sum of its proper divisors (13799847).

21122025 is a wasteful number, since it uses less digits than its factorization.

21122025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281640 (or 281635 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 15.

The square root of 21122025 is about 4595.8704289830. The cubic root of 21122025 is about 276.4257632660.

Adding to 21122025 its reverse (52022112), we get a palindrome (73144137).

The spelling of 21122025 in words is "twenty-one million, one hundred twenty-two thousand, twenty-five".