40015931 has 4 divisors (see below), whose sum is σ = 40056600. Its totient is φ = 39975264.

The previous prime is 40015903. The next prime is 40015961. The reversal of 40015931 is 13951004.

It is a happy number.

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 40015931 - 2⁶ = 40015867 is a prime.

It is a super-2 number, since 2×40015931² = 3202549467593522, 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 = 40015897 and 40015906.

It is not an unprimeable number, because it can be changed into a prime (40015961) 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, 18821 + ... + 20838.

It is an arithmetic number, because the mean of its divisors is an integer number (10014150).

Almost surely, 2^40015931 is an apocalyptic number.

40015931 is a deficient number, since it is larger than the sum of its proper divisors (40669).

40015931 is a wasteful number, since it uses less digits than its factorization.

40015931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40668.

The product of its (nonzero) digits is 540, while the sum is 23.

The square root of 40015931 is about 6325.8146510944. The cubic root of 40015931 is about 342.0405860204.

Adding to 40015931 its reverse (13951004), we get a palindrome (53966935).

The spelling of 40015931 in words is "forty million, fifteen thousand, nine hundred thirty-one".