21329679 has 16 divisors (see below), whose sum is σ = 34414848. Its totient is φ = 11471232.

The previous prime is 21329663. The next prime is 21329683. The reversal of 21329679 is 97692312.

It is not a de Polignac number, because 21329679 - 2⁴ = 21329663 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21329629) 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, 29517 + ... + 30230.

It is an arithmetic number, because the mean of its divisors is an integer number (2150928).

Almost surely, 2^21329679 is an apocalyptic number.

21329679 is a deficient number, since it is larger than the sum of its proper divisors (13085169).

21329679 is a wasteful number, since it uses less digits than its factorization.

21329679 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59774.

The product of its digits is 40824, while the sum is 39.

The square root of 21329679 is about 4618.4065433870. The cubic root of 21329679 is about 277.3286727533.

It can be divided in two parts, 2132 and 9679, that added together give a palindrome (11811).

The spelling of 21329679 in words is "twenty-one million, three hundred twenty-nine thousand, six hundred seventy-nine".