142521561 has 24 divisors (see below), whose sum is σ = 253373120. Its totient is φ = 75175776.

The previous prime is 142521553. The next prime is 142521563. The reversal of 142521561 is 165125241.

It is not a de Polignac number, because 142521561 - 2³ = 142521553 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (142521563) 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, 86191 + ... + 87828.

Almost surely, 2^142521561 is an apocalyptic number.

It is an amenable number.

142521561 is a deficient number, since it is larger than the sum of its proper divisors (110851559).

142521561 is a wasteful number, since it uses less digits than its factorization.

142521561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174045 (or 174042 counting only the distinct ones).

The product of its digits is 2400, while the sum is 27.

The square root of 142521561 is about 11938.2394430670. The cubic root of 142521561 is about 522.3483054367.

The spelling of 142521561 in words is "one hundred forty-two million, five hundred twenty-one thousand, five hundred sixty-one".