21159159 has 16 divisors (see below), whose sum is σ = 32312832. Its totient is φ = 12064608.

The previous prime is 21159133. The next prime is 21159161. The reversal of 21159159 is 95195112.

It is a happy number.

It is not a de Polignac number, because 21159159 - 2⁸ = 21158903 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21159109) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12942 + ... + 14484.

It is an arithmetic number, because the mean of its divisors is an integer number (2019552).

Almost surely, 2^21159159 is an apocalyptic number.

21159159 is a deficient number, since it is larger than the sum of its proper divisors (11153673).

21159159 is a wasteful number, since it uses less digits than its factorization.

21159159 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2206.

The product of its digits is 4050, while the sum is 33.

The square root of 21159159 is about 4599.9085860482. The cubic root of 21159159 is about 276.5876603813.

The spelling of 21159159 in words is "twenty-one million, one hundred fifty-nine thousand, one hundred fifty-nine".