142571521 has 4 divisors (see below), whose sum is σ = 143126532. Its totient is φ = 142016512.

The previous prime is 142571519. The next prime is 142571563. The reversal of 142571521 is 125175241.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 140090896 + 2480625 = 11836^2 + 1575^2 .

It is a cyclic number.

It is not a de Polignac number, because 142571521 - 2¹ = 142571519 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 142571521.

It is not an unprimeable number, because it can be changed into a prime (142571581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 277120 + ... + 277633.

It is an arithmetic number, because the mean of its divisors is an integer number (35781633).

Almost surely, 2^142571521 is an apocalyptic number.

It is an amenable number.

142571521 is a deficient number, since it is larger than the sum of its proper divisors (555011).

142571521 is an equidigital number, since it uses as much as digits as its factorization.

142571521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 555010.

The product of its digits is 2800, while the sum is 28.

The square root of 142571521 is about 11940.3316955602. The cubic root of 142571521 is about 522.4093335656.

The spelling of 142571521 in words is "one hundred forty-two million, five hundred seventy-one thousand, five hundred twenty-one".