142571981 has 2 divisors, whose sum is σ = 142571982. Its totient is φ = 142571980.

The previous prime is 142571971. The next prime is 142571983. The reversal of 142571981 is 189175241.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 131905225 + 10666756 = 11485^2 + 3266^2 .

It is a cyclic number.

It is not a de Polignac number, because 142571981 - 2¹⁸ = 142309837 is a prime.

It is a super-2 number, since 2×142571981² = 40653539532528722, which contains 22 as substring.

Together with 142571983, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (142571983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 71285990 + 71285991.

It is an arithmetic number, because the mean of its divisors is an integer number (71285991).

Almost surely, 2^142571981 is an apocalyptic number.

It is an amenable number.

142571981 is a deficient number, since it is larger than the sum of its proper divisors (1).

142571981 is an equidigital number, since it uses as much as digits as its factorization.

142571981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20160, while the sum is 38.

The square root of 142571981 is about 11940.3509579911. The cubic root of 142571981 is about 522.4098954077.

The spelling of 142571981 in words is "one hundred forty-two million, five hundred seventy-one thousand, nine hundred eighty-one".