17964272721 has 4 divisors (see below), whose sum is σ = 23952363632. Its totient is φ = 11976181812.

The previous prime is 17964272717. The next prime is 17964272731. The reversal of 17964272721 is 12727246971.

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 not a de Polignac number, because 17964272721 - 2² = 17964272717 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (17964272701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2994045451 + ... + 2994045456.

It is an arithmetic number, because the mean of its divisors is an integer number (5988090908).

Almost surely, 2^17964272721 is an apocalyptic number.

It is an amenable number.

17964272721 is a deficient number, since it is larger than the sum of its proper divisors (5988090911).

17964272721 is an equidigital number, since it uses as much as digits as its factorization.

17964272721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5988090910.

The product of its digits is 592704, while the sum is 48.

The spelling of 17964272721 in words is "seventeen billion, nine hundred sixty-four million, two hundred seventy-two thousand, seven hundred twenty-one".