42756731 has 4 divisors (see below), whose sum is σ = 42810264. Its totient is φ = 42703200.

The previous prime is 42756713. The next prime is 42756733. The reversal of 42756731 is 13765724.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 42756731 - 2¹⁸ = 42494587 is a prime.

It is a super-2 number, since 2×42756731² = 3656276091612722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 42756691 and 42756700.

It is not an unprimeable number, because it can be changed into a prime (42756733) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25550 + ... + 27171.

It is an arithmetic number, because the mean of its divisors is an integer number (10702566).

Almost surely, 2^42756731 is an apocalyptic number.

42756731 is a deficient number, since it is larger than the sum of its proper divisors (53533).

42756731 is an equidigital number, since it uses as much as digits as its factorization.

42756731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53532.

The product of its digits is 35280, while the sum is 35.

The square root of 42756731 is about 6538.8631274863. The cubic root of 42756731 is about 349.6778832279.

The spelling of 42756731 in words is "forty-two million, seven hundred fifty-six thousand, seven hundred thirty-one".