31144323531 has 4 divisors (see below), whose sum is σ = 41525764712. Its totient is φ = 20762882352.

The previous prime is 31144323523. The next prime is 31144323533. The reversal of 31144323531 is 13532344113.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 31144323531 - 2³ = 31144323523 is a prime.

It is a super-2 number, since 2×31144323531² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31144323533) 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, 5190720586 + ... + 5190720591.

It is an arithmetic number, because the mean of its divisors is an integer number (10381441178).

Almost surely, 2^31144323531 is an apocalyptic number.

31144323531 is a deficient number, since it is larger than the sum of its proper divisors (10381441181).

31144323531 is a wasteful number, since it uses less digits than its factorization.

31144323531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10381441180.

The product of its digits is 12960, while the sum is 30.

Adding to 31144323531 its reverse (13532344113), we get a palindrome (44676667644).

The spelling of 31144323531 in words is "thirty-one billion, one hundred forty-four million, three hundred twenty-three thousand, five hundred thirty-one".