21172580753 has 4 divisors (see below), whose sum is σ = 21201077568. Its totient is φ = 21144083940.

The previous prime is 21172580711. The next prime is 21172580771. The reversal of 21172580753 is 35708527112.

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 not a de Polignac number, because 21172580753 - 2²⁶ = 21105471889 is a prime.

It is a super-3 number, since 3×21172580753³ (a number of 32 digits) contains 333 as substring.

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 21172580753.

It is not an unprimeable number, because it can be changed into a prime (21172520753) 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, 14247293 + ... + 14248778.

It is an arithmetic number, because the mean of its divisors is an integer number (5300269392).

Almost surely, 2^21172580753 is an apocalyptic number.

It is an amenable number.

21172580753 is a deficient number, since it is larger than the sum of its proper divisors (28496815).

21172580753 is an equidigital number, since it uses as much as digits as its factorization.

21172580753 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28496814.

The product of its (nonzero) digits is 117600, while the sum is 41.

The spelling of 21172580753 in words is "twenty-one billion, one hundred seventy-two million, five hundred eighty thousand, seven hundred fifty-three".