142149781 has 2 divisors, whose sum is σ = 142149782. Its totient is φ = 142149780.

The previous prime is 142149769. The next prime is 142149817. The reversal of 142149781 is 187941241.

Together with next prime (142149817) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71740900 + 70408881 = 8470^2 + 8391^2 .

It is a cyclic number.

It is not a de Polignac number, because 142149781 - 2⁷ = 142149653 is a prime.

It is a super-2 number, since 2×142149781² = 40413120476695922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 142149781.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (142149731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 71074890 + 71074891.

It is an arithmetic number, because the mean of its divisors is an integer number (71074891).

Almost surely, 2^142149781 is an apocalyptic number.

It is an amenable number.

142149781 is a deficient number, since it is larger than the sum of its proper divisors (1).

142149781 is an equidigital number, since it uses as much as digits as its factorization.

142149781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 16128, while the sum is 37.

The square root of 142149781 is about 11922.6583025767. The cubic root of 142149781 is about 521.8937127931.

The spelling of 142149781 in words is "one hundred forty-two million, one hundred forty-nine thousand, seven hundred eighty-one".