21225579 has 8 divisors (see below), whose sum is σ = 28343952. Its totient is φ = 14128800.

The previous prime is 21225563. The next prime is 21225583. The reversal of 21225579 is 97552212.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21225579 - 2⁴ = 21225563 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21225559) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2944 + ... + 7149.

It is an arithmetic number, because the mean of its divisors is an integer number (3542994).

Almost surely, 2^21225579 is an apocalyptic number.

21225579 is a deficient number, since it is larger than the sum of its proper divisors (7118373).

21225579 is a wasteful number, since it uses less digits than its factorization.

21225579 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10797.

The product of its digits is 12600, while the sum is 33.

The square root of 21225579 is about 4607.1226378294. The cubic root of 21225579 is about 276.8767670720.

The spelling of 21225579 in words is "twenty-one million, two hundred twenty-five thousand, five hundred seventy-nine".