21679029 has 32 divisors (see below), whose sum is σ = 34525440. Its totient is φ = 13395456.

The previous prime is 21679001. The next prime is 21679033. The reversal of 21679029 is 92097612.

It is not a de Polignac number, because 21679029 - 2¹¹ = 21676981 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21678984 and 21679002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21679039) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 33184 + ... + 33830.

It is an arithmetic number, because the mean of its divisors is an integer number (1078920).

Almost surely, 2^21679029 is an apocalyptic number.

It is an amenable number.

21679029 is a deficient number, since it is larger than the sum of its proper divisors (12846411).

21679029 is a wasteful number, since it uses less digits than its factorization.

21679029 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 746 (or 740 counting only the distinct ones).

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

The square root of 21679029 is about 4656.0744195083. The cubic root of 21679029 is about 278.8345648902.

The spelling of 21679029 in words is "twenty-one million, six hundred seventy-nine thousand, twenty-nine".