142189561 has 2 divisors, whose sum is σ = 142189562. Its totient is φ = 142189560.

The previous prime is 142189507. The next prime is 142189573. The reversal of 142189561 is 165981241.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 107744400 + 34445161 = 10380^2 + 5869^2 .

It is an emirp because it is prime and its reverse (165981241) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 142189561 - 2²⁷ = 7971833 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 142189561.

It is not a weakly prime, because it can be changed into another prime (142189661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 71094780 + 71094781.

It is an arithmetic number, because the mean of its divisors is an integer number (71094781).

Almost surely, 2^142189561 is an apocalyptic number.

It is an amenable number.

142189561 is a deficient number, since it is larger than the sum of its proper divisors (1).

142189561 is an equidigital number, since it uses as much as digits as its factorization.

142189561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17280, while the sum is 37.

The square root of 142189561 is about 11924.3264380006. The cubic root of 142189561 is about 521.9423914836.

The spelling of 142189561 in words is "one hundred forty-two million, one hundred eighty-nine thousand, five hundred sixty-one".