42912531 has 16 divisors (see below), whose sum is σ = 63759520. Its totient is φ = 28524960.

The previous prime is 42912523. The next prime is 42912553. The reversal of 42912531 is 13521924.

42912531 is a `hidden beast` number, since 42 + 91 + 2 + 531 = 666.

42912531 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 42912531 - 2³ = 42912523 is a prime.

It is a super-2 number, since 2×42912531² = 3682970633651922, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 42912495 and 42912504.

It is not an unprimeable number, because it can be changed into a prime (42912511) 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 15 ways as a sum of consecutive naturals, for example, 7941 + ... + 12201.

It is an arithmetic number, because the mean of its divisors is an integer number (3984970).

Almost surely, 2^42912531 is an apocalyptic number.

42912531 is a deficient number, since it is larger than the sum of its proper divisors (20846989).

42912531 is a wasteful number, since it uses less digits than its factorization.

42912531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4643 (or 4637 counting only the distinct ones).

The product of its digits is 2160, while the sum is 27.

The square root of 42912531 is about 6550.7656804377. The cubic root of 42912531 is about 350.1020953858.

The spelling of 42912531 in words is "forty-two million, nine hundred twelve thousand, five hundred thirty-one".