31440031 has 8 divisors (see below), whose sum is σ = 37170720. Its totient is φ = 26019168.

The previous prime is 31440001. The next prime is 31440049. The reversal of 31440031 is 13004413.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 31440031 - 2²¹ = 29342879 is a prime.

It is a super-2 number, since 2×31440031² = 1976951098561922, 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 = 31439987 and 31440014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31440001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 77236 + ... + 77641.

It is an arithmetic number, because the mean of its divisors is an integer number (4646340).

Almost surely, 2^31440031 is an apocalyptic number.

31440031 is a deficient number, since it is larger than the sum of its proper divisors (5730689).

31440031 is a wasteful number, since it uses less digits than its factorization.

31440031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154913.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 31440031 is about 5607.1410718832. The cubic root of 31440031 is about 315.6174368151.

Adding to 31440031 its reverse (13004413), we get a palindrome (44444444).

The spelling of 31440031 in words is "thirty-one million, four hundred forty thousand, thirty-one".