42187631 has 2 divisors, whose sum is σ = 42187632. Its totient is φ = 42187630.

The previous prime is 42187597. The next prime is 42187637. The reversal of 42187631 is 13678124.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 42187631 - 2¹⁸ = 41925487 is a prime.

It is a super-2 number, since 2×42187631² = 3559592418784322, which contains 22 as substring.

It is equal to p_2558327 and since 42187631 and 2558327 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42187637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21093815 + 21093816.

It is an arithmetic number, because the mean of its divisors is an integer number (21093816).

Almost surely, 2^42187631 is an apocalyptic number.

42187631 is a deficient number, since it is larger than the sum of its proper divisors (1).

42187631 is an equidigital number, since it uses as much as digits as its factorization.

42187631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8064, while the sum is 32.

The square root of 42187631 is about 6495.2006127602. The cubic root of 42187631 is about 348.1195228454.

The spelling of 42187631 in words is "forty-two million, one hundred eighty-seven thousand, six hundred thirty-one".