31115145 has 16 divisors (see below), whose sum is σ = 49896000. Its totient is φ = 16557504.

The previous prime is 31115129. The next prime is 31115191. The reversal of 31115145 is 54151113.

It is a happy number.

It is not a de Polignac number, because 31115145 - 2⁴ = 31115129 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5407 + ... + 9563.

It is an arithmetic number, because the mean of its divisors is an integer number (3118500).

Almost surely, 2^31115145 is an apocalyptic number.

It is an amenable number.

31115145 is a deficient number, since it is larger than the sum of its proper divisors (18780855).

31115145 is a wasteful number, since it uses less digits than its factorization.

31115145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4664.

The product of its digits is 300, while the sum is 21.

The square root of 31115145 is about 5578.0951049619. The cubic root of 31115145 is about 314.5265247574.

Adding to 31115145 its reverse (54151113), we get a palindrome (85266258).

It can be divided in two parts, 3111 and 5145, that added together give a triangular number (8256 = T₁₂₈).

The spelling of 31115145 in words is "thirty-one million, one hundred fifteen thousand, one hundred forty-five".