21131759573 has 4 divisors (see below), whose sum is σ = 21132094368. Its totient is φ = 21131424780.

The previous prime is 21131759513. The next prime is 21131759633. The reversal of 21131759573 is 37595713112.

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 an interprime number because it is at equal distance from previous prime (21131759513) and next prime (21131759633).

It is a cyclic number.

It is not a de Polignac number, because 21131759573 - 2²⁶ = 21064650709 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 (21131759513) 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, 40811 + ... + 209592.

It is an arithmetic number, because the mean of its divisors is an integer number (5283023592).

Almost surely, 2^21131759573 is an apocalyptic number.

It is an amenable number.

21131759573 is a deficient number, since it is larger than the sum of its proper divisors (334795).

21131759573 is an equidigital number, since it uses as much as digits as its factorization.

21131759573 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 334794.

The product of its digits is 198450, while the sum is 44.

The spelling of 21131759573 in words is "twenty-one billion, one hundred thirty-one million, seven hundred fifty-nine thousand, five hundred seventy-three".