21223125 has 120 divisors (see below), whose sum is σ = 48734400. Its totient is φ = 8820000.

The previous prime is 21223093. The next prime is 21223141. The reversal of 21223125 is 52132212.

It is not a de Polignac number, because 21223125 - 2⁵ = 21223093 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21223098 and 21223107.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 1929370 + ... + 1929380.

It is an arithmetic number, because the mean of its divisors is an integer number (406120).

Almost surely, 2^21223125 is an apocalyptic number.

21223125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21223125 is an abundant number, since it is smaller than the sum of its proper divisors (27511275).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21223125 is an equidigital number, since it uses as much as digits as its factorization.

21223125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58 (or 26 counting only the distinct ones).

The product of its digits is 240, while the sum is 18.

The square root of 21223125 is about 4606.8563033809. The cubic root of 21223125 is about 276.8660962713.

Adding to 21223125 its reverse (52132212), we get a palindrome (73355337).

The spelling of 21223125 in words is "twenty-one million, two hundred twenty-three thousand, one hundred twenty-five".