21612479 has 24 divisors (see below), whose sum is σ = 26615808. Its totient is φ = 17463600.

The previous prime is 21612431. The next prime is 21612497. The reversal of 21612479 is 97421612.

It is a happy number.

It is not a de Polignac number, because 21612479 - 2¹² = 21608383 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21612079) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 143054 + ... + 143204.

It is an arithmetic number, because the mean of its divisors is an integer number (1108992).

Almost surely, 2^21612479 is an apocalyptic number.

21612479 is a deficient number, since it is larger than the sum of its proper divisors (5003329).

21612479 is a wasteful number, since it uses less digits than its factorization.

21612479 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 315 (or 308 counting only the distinct ones).

The product of its digits is 6048, while the sum is 32.

The square root of 21612479 is about 4648.9223482437. The cubic root of 21612479 is about 278.5489515317.

The spelling of 21612479 in words is "twenty-one million, six hundred twelve thousand, four hundred seventy-nine".