40399031 has 4 divisors (see below), whose sum is σ = 40412064. Its totient is φ = 40386000.

The previous prime is 40398977. The next prime is 40399039. The reversal of 40399031 is 13099304.

40399031 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40399031 is a prime.

It is a super-2 number, since 2×40399031² = 3264163411477922, 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 = 40398985 and 40399003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40399039) 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 3 ways as a sum of consecutive naturals, for example, 1106 + ... + 9056.

It is an arithmetic number, because the mean of its divisors is an integer number (10103016).

Almost surely, 2^40399031 is an apocalyptic number.

40399031 is the 2843-rd centered decagonal number.

40399031 is a deficient number, since it is larger than the sum of its proper divisors (13033).

40399031 is an equidigital number, since it uses as much as digits as its factorization.

40399031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13032.

The product of its (nonzero) digits is 2916, while the sum is 29.

The square root of 40399031 is about 6356.0232063768. The cubic root of 40399031 is about 343.1286509499.

The spelling of 40399031 in words is "forty million, three hundred ninety-nine thousand, thirty-one".