31440172 has 24 divisors (see below), whose sum is σ = 57609216. Its totient is φ = 14985168.

The previous prime is 31440161. The next prime is 31440173. The reversal of 31440172 is 27104413.

It is not an unprimeable number, because it can be changed into a prime (31440173) 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 in 7 ways as a sum of consecutive naturals, for example, 51493 + ... + 52099.

It is an arithmetic number, because the mean of its divisors is an integer number (2400384).

Almost surely, 2^31440172 is an apocalyptic number.

It is an amenable number.

31440172 is a deficient number, since it is larger than the sum of its proper divisors (26169044).

31440172 is a wasteful number, since it uses less digits than its factorization.

31440172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1197 (or 1195 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 31440172 is about 5607.1536451216. The cubic root of 31440172 is about 315.6179086339.

Adding to 31440172 its reverse (27104413), we get a palindrome (58544585).

The spelling of 31440172 in words is "thirty-one million, four hundred forty thousand, one hundred seventy-two".