42681591 has 18 divisors (see below), whose sum is σ = 63861720. Its totient is φ = 27468336.

The previous prime is 42681563. The next prime is 42681599. The reversal of 42681591 is 19518624.

42681591 is a `hidden beast` number, since 4 + 2 + 68 + 1 + 591 = 666.

It is not a de Polignac number, because 42681591 - 2⁵ = 42681559 is a prime.

It is a super-3 number, since 3×42681591³ (a number of 24 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42681599) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 4750 + ... + 10388.

Almost surely, 2^42681591 is an apocalyptic number.

42681591 is a deficient number, since it is larger than the sum of its proper divisors (21180129).

42681591 is a wasteful number, since it uses less digits than its factorization.

42681591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5703 (or 5671 counting only the distinct ones).

The product of its digits is 17280, while the sum is 36.

The square root of 42681591 is about 6533.1149538333. The cubic root of 42681591 is about 349.4729236639.

The spelling of 42681591 in words is "forty-two million, six hundred eighty-one thousand, five hundred ninety-one".