42131989 has 2 divisors, whose sum is σ = 42131990. Its totient is φ = 42131988.

The previous prime is 42131981. The next prime is 42132017. The reversal of 42131989 is 98913124.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27562500 + 14569489 = 5250^2 + 3817^2 .

It is a cyclic number.

It is not a de Polignac number, because 42131989 - 2³ = 42131981 is a prime.

It is a super-2 number, since 2×42131989² = 3550208994192242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42131981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21065994 + 21065995.

It is an arithmetic number, because the mean of its divisors is an integer number (21065995).

Almost surely, 2^42131989 is an apocalyptic number.

It is an amenable number.

42131989 is a deficient number, since it is larger than the sum of its proper divisors (1).

42131989 is an equidigital number, since it uses as much as digits as its factorization.

42131989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15552, while the sum is 37.

The square root of 42131989 is about 6490.9158829860. The cubic root of 42131989 is about 347.9664085469.

The spelling of 42131989 in words is "forty-two million, one hundred thirty-one thousand, nine hundred eighty-nine".