15221272723 has 4 divisors (see below), whose sum is σ = 16022392360. Its totient is φ = 14420153088.

The previous prime is 15221272687. The next prime is 15221272727. The reversal of 15221272723 is 32727212251.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15221272723 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15221272727) 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, 400559790 + ... + 400559827.

It is an arithmetic number, because the mean of its divisors is an integer number (4005598090).

Almost surely, 2^15221272723 is an apocalyptic number.

15221272723 is a deficient number, since it is larger than the sum of its proper divisors (801119637).

15221272723 is an equidigital number, since it uses as much as digits as its factorization.

15221272723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 801119636.

The product of its digits is 23520, while the sum is 34.

Adding to 15221272723 its reverse (32727212251), we get a palindrome (47948484974).

The spelling of 15221272723 in words is "fifteen billion, two hundred twenty-one million, two hundred seventy-two thousand, seven hundred twenty-three".