21601079 has 4 divisors (see below), whose sum is σ = 22297920. Its totient is φ = 20904240.

The previous prime is 21601061. The next prime is 21601121. The reversal of 21601079 is 97010612.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21601079 - 2⁸ = 21600823 is a prime.

It is a super-2 number, since 2×21601079² = 933213227928482, which contains 22 as substring.

It is a Duffinian number.

It is a zygodrome in base 3.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21601579) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 348374 + ... + 348435.

It is an arithmetic number, because the mean of its divisors is an integer number (5574480).

Almost surely, 2^21601079 is an apocalyptic number.

21601079 is a deficient number, since it is larger than the sum of its proper divisors (696841).

21601079 is an equidigital number, since it uses as much as digits as its factorization.

21601079 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 696840.

The product of its (nonzero) digits is 756, while the sum is 26.

The square root of 21601079 is about 4647.6960959168. The cubic root of 21601079 is about 278.4999672306.

The spelling of 21601079 in words is "twenty-one million, six hundred one thousand, seventy-nine".