21498879 has 8 divisors (see below), whose sum is σ = 28686592. Its totient is φ = 14321880.

The previous prime is 21498857. The next prime is 21498907. The reversal of 21498879 is 97889412.

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

It is not a de Polignac number, because 21498879 - 2⁵ = 21498847 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 (21498679) 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, 6672 + ... + 9354.

It is an arithmetic number, because the mean of its divisors is an integer number (3585824).

Almost surely, 2^21498879 is an apocalyptic number.

21498879 is a deficient number, since it is larger than the sum of its proper divisors (7187713).

21498879 is a wasteful number, since it uses less digits than its factorization.

21498879 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5357.

The product of its digits is 290304, while the sum is 48.

The square root of 21498879 is about 4636.6883656334. The cubic root of 21498879 is about 278.0600555174.

The spelling of 21498879 in words is "twenty-one million, four hundred ninety-eight thousand, eight hundred seventy-nine".