21290679 has 6 divisors (see below), whose sum is σ = 30753216. Its totient is φ = 14193780.

The previous prime is 21290653. The next prime is 21290693. The reversal of 21290679 is 97609212.

It is not a de Polignac number, because 21290679 - 2⁷ = 21290551 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21290609) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1182807 + ... + 1182824.

It is an arithmetic number, because the mean of its divisors is an integer number (5125536).

Almost surely, 2^21290679 is an apocalyptic number.

21290679 is a deficient number, since it is larger than the sum of its proper divisors (9462537).

21290679 is a wasteful number, since it uses less digits than its factorization.

21290679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2365637 (or 2365634 counting only the distinct ones).

The product of its (nonzero) digits is 13608, while the sum is 36.

The square root of 21290679 is about 4614.1823761096. The cubic root of 21290679 is about 277.1595435170.

The spelling of 21290679 in words is "twenty-one million, two hundred ninety thousand, six hundred seventy-nine".