21573465079 has 2 divisors, whose sum is σ = 21573465080. Its totient is φ = 21573465078.

The previous prime is 21573465077. The next prime is 21573465097. The reversal of 21573465079 is 97056437512.

Together with next prime (21573465097) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21573465079 - 2¹ = 21573465077 is a prime.

Together with 21573465077, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21573465077) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10786732539 + 10786732540.

It is an arithmetic number, because the mean of its divisors is an integer number (10786732540).

Almost surely, 2^21573465079 is an apocalyptic number.

21573465079 is a deficient number, since it is larger than the sum of its proper divisors (1).

21573465079 is an equidigital number, since it uses as much as digits as its factorization.

21573465079 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1587600, while the sum is 49.

The spelling of 21573465079 in words is "twenty-one billion, five hundred seventy-three million, four hundred sixty-five thousand, seventy-nine".