166724627721 has 16 divisors (see below), whose sum is σ = 223010983104. Its totient is φ = 110794166784.

The previous prime is 166724627701. The next prime is 166724627753. The reversal of 166724627721 is 127726427661.

It is not a de Polignac number, because 166724627721 - 2¹¹ = 166724625673 is a prime.

It is not an unprimeable number, because it can be changed into a prime (166724627701) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4974606 + ... + 5008008.

It is an arithmetic number, because the mean of its divisors is an integer number (13938186444).

Almost surely, 2^166724627721 is an apocalyptic number.

It is an amenable number.

166724627721 is a deficient number, since it is larger than the sum of its proper divisors (56286355383).

166724627721 is a wasteful number, since it uses less digits than its factorization.

166724627721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38680.

The product of its digits is 2370816, while the sum is 51.

The spelling of 166724627721 in words is "one hundred sixty-six billion, seven hundred twenty-four million, six hundred twenty-seven thousand, seven hundred twenty-one".