31253661 has 16 divisors (see below), whose sum is σ = 46576320. Its totient is φ = 20712240.

The previous prime is 31253639. The next prime is 31253669. The reversal of 31253661 is 16635213.

It is not a de Polignac number, because 31253661 - 2⁶ = 31253597 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31253669) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1326 + ... + 8016.

It is an arithmetic number, because the mean of its divisors is an integer number (2911020).

Almost surely, 2^31253661 is an apocalyptic number.

It is an amenable number.

31253661 is a deficient number, since it is larger than the sum of its proper divisors (15322659).

31253661 is a wasteful number, since it uses less digits than its factorization.

31253661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6873 (or 6867 counting only the distinct ones).

The product of its digits is 3240, while the sum is 27.

The square root of 31253661 is about 5590.4973839543. The cubic root of 31253661 is about 314.9925621827.

Adding to 31253661 its reverse (16635213), we get a palindrome (47888874).

It can be divided in two parts, 3125 and 3661, that added together give a triangular number (6786 = T₁₁₆).

The spelling of 31253661 in words is "thirty-one million, two hundred fifty-three thousand, six hundred sixty-one".