21364360561573 has 4 divisors (see below), whose sum is σ = 21460164869248. Its totient is φ = 21268556253900.

The previous prime is 21364360561547. The next prime is 21364360561619. The reversal of 21364360561573 is 37516506346312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21364360561573 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21364360561573.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21364360561273) 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, 47902153503 + ... + 47902153948.

It is an arithmetic number, because the mean of its divisors is an integer number (5365041217312).

Almost surely, 2^{21364360561573} is an apocalyptic number.

It is an amenable number.

21364360561573 is a deficient number, since it is larger than the sum of its proper divisors (95804307675).

21364360561573 is an equidigital number, since it uses as much as digits as its factorization.

21364360561573 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95804307674.

The product of its (nonzero) digits is 8164800, while the sum is 52.

The spelling of 21364360561573 in words is "twenty-one trillion, three hundred sixty-four billion, three hundred sixty million, five hundred sixty-one thousand, five hundred seventy-three".