21696079 has 2 divisors, whose sum is σ = 21696080. Its totient is φ = 21696078.

The previous prime is 21696041. The next prime is 21696083. The reversal of 21696079 is 97069612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21696079 - 2¹¹ = 21694031 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21696019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10848039 + 10848040.

It is an arithmetic number, because the mean of its divisors is an integer number (10848040).

Almost surely, 2^21696079 is an apocalyptic number.

21696079 is a deficient number, since it is larger than the sum of its proper divisors (1).

21696079 is an equidigital number, since it uses as much as digits as its factorization.

21696079 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40824, while the sum is 40.

The square root of 21696079 is about 4657.9050011781. The cubic root of 21696079 is about 278.9076444785.

The spelling of 21696079 in words is "twenty-one million, six hundred ninety-six thousand, seventy-nine".