21600079 has 4 divisors (see below), whose sum is σ = 21684384. Its totient is φ = 21515776.

The previous prime is 21600037. The next prime is 21600091. The reversal of 21600079 is 97000612.

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 21600079 - 2⁷ = 21599951 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21600479) 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, 41767 + ... + 42280.

It is an arithmetic number, because the mean of its divisors is an integer number (5421096).

Almost surely, 2^21600079 is an apocalyptic number.

21600079 is a deficient number, since it is larger than the sum of its proper divisors (84305).

21600079 is an equidigital number, since it uses as much as digits as its factorization.

21600079 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84304.

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 21600079 is about 4647.5885144879. The cubic root of 21600079 is about 278.4956695400.

The spelling of 21600079 in words is "twenty-one million, six hundred thousand, seventy-nine".