21479051 has 4 divisors (see below), whose sum is σ = 23431704. Its totient is φ = 19526400.

The previous prime is 21479027. The next prime is 21479057. The reversal of 21479051 is 15097412.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21479051 is a prime.

It is a super-2 number, since 2×21479051² = 922699263721202, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21479057) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 976310 + ... + 976331.

It is an arithmetic number, because the mean of its divisors is an integer number (5857926).

Almost surely, 2^21479051 is an apocalyptic number.

21479051 is a deficient number, since it is larger than the sum of its proper divisors (1952653).

21479051 is a wasteful number, since it uses less digits than its factorization.

21479051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1952652.

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 21479051 is about 4634.5497084399. The cubic root of 21479051 is about 277.9745460883.

The spelling of 21479051 in words is "twenty-one million, four hundred seventy-nine thousand, fifty-one".