11662724721 has 4 divisors (see below), whose sum is σ = 15550299632. Its totient is φ = 7775149812.

The previous prime is 11662724719. The next prime is 11662724753. The reversal of 11662724721 is 12742726611.

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 11662724721 - 2¹ = 11662724719 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 11662724721.

It is not an unprimeable number, because it can be changed into a prime (11662724771) 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, 1943787451 + ... + 1943787456.

It is an arithmetic number, because the mean of its divisors is an integer number (3887574908).

Almost surely, 2^11662724721 is an apocalyptic number.

It is an amenable number.

11662724721 is a deficient number, since it is larger than the sum of its proper divisors (3887574911).

11662724721 is an equidigital number, since it uses as much as digits as its factorization.

11662724721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3887574910.

The product of its digits is 56448, while the sum is 39.

The spelling of 11662724721 in words is "eleven billion, six hundred sixty-two million, seven hundred twenty-four thousand, seven hundred twenty-one".