31243249 has 2 divisors, whose sum is σ = 31243250. Its totient is φ = 31243248.

The previous prime is 31243231. The next prime is 31243253. The reversal of 31243249 is 94234213.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30724849 + 518400 = 5543^2 + 720^2 .

It is a cyclic number.

It is not a de Polignac number, because 31243249 - 2⁵ = 31243217 is a prime.

It is a super-2 number, since 2×31243249² = 1952281216152002, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31243279) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15621624 + 15621625.

It is an arithmetic number, because the mean of its divisors is an integer number (15621625).

Almost surely, 2^31243249 is an apocalyptic number.

It is an amenable number.

31243249 is a deficient number, since it is larger than the sum of its proper divisors (1).

31243249 is an equidigital number, since it uses as much as digits as its factorization.

31243249 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5184, while the sum is 28.

The square root of 31243249 is about 5589.5660833378. The cubic root of 31243249 is about 314.9575789015.

It can be divided in two parts, 312432 and 49, that added together give a square (312481 = 559²).

The spelling of 31243249 in words is "thirty-one million, two hundred forty-three thousand, two hundred forty-nine".