187748579721 has 24 divisors (see below), whose sum is σ = 262514851200. Its totient is φ = 119345734816.

The previous prime is 187748579719. The next prime is 187748579731. The reversal of 187748579721 is 127975847781.

It is not a de Polignac number, because 187748579721 - 2¹ = 187748579719 is a prime.

It is not an unprimeable number, because it can be changed into a prime (187748579701) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 316480 + ... + 689678.

It is an arithmetic number, because the mean of its divisors is an integer number (10938118800).

Almost surely, 2^187748579721 is an apocalyptic number.

It is an amenable number.

187748579721 is a deficient number, since it is larger than the sum of its proper divisors (74766271479).

187748579721 is a wasteful number, since it uses less digits than its factorization.

187748579721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 373565 (or 373542 counting only the distinct ones).

The product of its digits is 55319040, while the sum is 66.

The spelling of 187748579721 in words is "one hundred eighty-seven billion, seven hundred forty-eight million, five hundred seventy-nine thousand, seven hundred twenty-one".