21052879 has 4 divisors (see below), whose sum is σ = 21213720. Its totient is φ = 20892040.

The previous prime is 21052877. The next prime is 21052907. The reversal of 21052879 is 97825012.

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 21052879 - 2¹ = 21052877 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 (21052877) 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, 80224 + ... + 80485.

It is an arithmetic number, because the mean of its divisors is an integer number (5303430).

Almost surely, 2^21052879 is an apocalyptic number.

21052879 is a deficient number, since it is larger than the sum of its proper divisors (160841).

21052879 is a wasteful number, since it uses less digits than its factorization.

21052879 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160840.

The product of its (nonzero) digits is 10080, while the sum is 34.

The square root of 21052879 is about 4588.3416394161. The cubic root of 21052879 is about 276.1237936232.

The spelling of 21052879 in words is "twenty-one million, fifty-two thousand, eight hundred seventy-nine".