142174997721 has 9 divisors (see below), whose sum is σ = 205365519541. Its totient is φ = 94782577692.

The previous prime is 142174997707. The next prime is 142174997729. The reversal of 142174997721 is 127799471241.

The square root of 142174997721 is 377061.

It is a perfect power (a square), and thus also a powerful number.

142174997721 is a `hidden beast` number, since 142 + 1 + 7 + 499 + 7 + 7 + 2 + 1 = 666.

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 142174997721 - 2⁷ = 142174997593 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (142174997729) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1068340 + ... + 1194026.

Almost surely, 2^142174997721 is an apocalyptic number.

142174997721 is the 377061-st square number.

142174997721 is the 188531-st centered octagonal number.

It is an amenable number.

142174997721 is a deficient number, since it is larger than the sum of its proper divisors (63190521820).

142174997721 is an frugal number, since it uses more digits than its factorization.

142174997721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 251380 (or 125690 counting only the distinct ones).

The product of its digits is 1778112, while the sum is 54.

The spelling of 142174997721 in words is "one hundred forty-two billion, one hundred seventy-four million, nine hundred ninety-seven thousand, seven hundred twenty-one".