42137991 has 72 divisors (see below), whose sum is σ = 76826880. Its totient is φ = 22117536.

The previous prime is 42137981. The next prime is 42137993. The reversal of 42137991 is 19973124.

42137991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 42137991 - 2¹³ = 42129799 is a prime.

It is a super-2 number, since 2×42137991² = 3551220571032162, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42137993) 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 71 ways as a sum of consecutive naturals, for example, 393760 + ... + 393866.

It is an arithmetic number, because the mean of its divisors is an integer number (1067040).

Almost surely, 2^42137991 is an apocalyptic number.

42137991 is a deficient number, since it is larger than the sum of its proper divisors (34688889).

42137991 is a wasteful number, since it uses less digits than its factorization.

42137991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 193 (or 183 counting only the distinct ones).

The product of its digits is 13608, while the sum is 36.

The square root of 42137991 is about 6491.3782049731. The cubic root of 42137991 is about 347.9829311882.

The spelling of 42137991 in words is "forty-two million, one hundred thirty-seven thousand, nine hundred ninety-one".