31531012 has 6 divisors (see below), whose sum is σ = 55179278. Its totient is φ = 15765504.

The previous prime is 31531001. The next prime is 31531057. The reversal of 31531012 is 21013513.

It can be written as a sum of positive squares in only one way, i.e., 29746116 + 1784896 = 5454^2 + 1336^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3941373 + ... + 3941380.

Almost surely, 2^31531012 is an apocalyptic number.

It is an amenable number.

31531012 is a deficient number, since it is larger than the sum of its proper divisors (23648266).

31531012 is a wasteful number, since it uses less digits than its factorization.

31531012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7882757 (or 7882755 counting only the distinct ones).

The product of its (nonzero) digits is 90, while the sum is 16.

The square root of 31531012 is about 5615.2481690483. The cubic root of 31531012 is about 315.9215876586.

Adding to 31531012 its reverse (21013513), we get a palindrome (52544525).

The spelling of 31531012 in words is "thirty-one million, five hundred thirty-one thousand, twelve".