21023179 has 4 divisors (see below), whose sum is σ = 21133440. Its totient is φ = 20912920.

The previous prime is 21023161. The next prime is 21023183. The reversal of 21023179 is 97132012.

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

It is a cyclic number.

It is not a de Polignac number, because 21023179 - 2²³ = 12634571 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21023279) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 54844 + ... + 55225.

It is an arithmetic number, because the mean of its divisors is an integer number (5283360).

Almost surely, 2^21023179 is an apocalyptic number.

21023179 is a deficient number, since it is larger than the sum of its proper divisors (110261).

21023179 is a wasteful number, since it uses less digits than its factorization.

21023179 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110260.

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 21023179 is about 4585.1040337161. The cubic root of 21023179 is about 275.9938868281.

The spelling of 21023179 in words is "twenty-one million, twenty-three thousand, one hundred seventy-nine".