42979831 has 2 divisors, whose sum is σ = 42979832. Its totient is φ = 42979830.

The previous prime is 42979823. The next prime is 42979837. The reversal of 42979831 is 13897924.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 42979831 - 2³ = 42979823 is a prime.

It is a super-2 number, since 2×42979831² = 3694531745577122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42979837) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21489915 + 21489916.

It is an arithmetic number, because the mean of its divisors is an integer number (21489916).

Almost surely, 2^42979831 is an apocalyptic number.

42979831 is a deficient number, since it is larger than the sum of its proper divisors (1).

42979831 is an equidigital number, since it uses as much as digits as its factorization.

42979831 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108864, while the sum is 43.

The square root of 42979831 is about 6555.9004720938. The cubic root of 42979831 is about 350.2850222511.

The spelling of 42979831 in words is "forty-two million, nine hundred seventy-nine thousand, eight hundred thirty-one".