31242644 has 6 divisors (see below), whose sum is σ = 54674634. Its totient is φ = 15621320.

The previous prime is 31242643. The next prime is 31242661. The reversal of 31242644 is 44624213.

It can be written as a sum of positive squares in only one way, i.e., 31225744 + 16900 = 5588^2 + 130^2 .

It is a super-2 number, since 2×31242644² = 1952205608221472, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31242641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3905327 + ... + 3905334.

It is an arithmetic number, because the mean of its divisors is an integer number (9112439).

Almost surely, 2^31242644 is an apocalyptic number.

It is an amenable number.

31242644 is a deficient number, since it is larger than the sum of its proper divisors (23431990).

31242644 is a wasteful number, since it uses less digits than its factorization.

31242644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7810665 (or 7810663 counting only the distinct ones).

The product of its digits is 4608, while the sum is 26.

The square root of 31242644 is about 5589.5119643847. The cubic root of 31242644 is about 314.9555459229.

Adding to 31242644 its reverse (44624213), we get a palindrome (75866857).

The spelling of 31242644 in words is "thirty-one million, two hundred forty-two thousand, six hundred forty-four".