31249993 has 2 divisors, whose sum is σ = 31249994. Its totient is φ = 31249992.

The previous prime is 31249991. The next prime is 31249997. The reversal of 31249993 is 39994213.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24681024 + 6568969 = 4968^2 + 2563^2 .

It is a cyclic number.

It is not a de Polignac number, because 31249993 - 2¹ = 31249991 is a prime.

Together with 31249991, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (31249991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15624996 + 15624997.

It is an arithmetic number, because the mean of its divisors is an integer number (15624997).

Almost surely, 2^31249993 is an apocalyptic number.

It is an amenable number.

31249993 is a deficient number, since it is larger than the sum of its proper divisors (1).

31249993 is an equidigital number, since it uses as much as digits as its factorization.

31249993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 52488, while the sum is 40.

The square root of 31249993 is about 5590.1693176504. The cubic root of 31249993 is about 314.9802389552.

It can be divided in two parts, 312 and 49993, that added together give a palindrome (50305).

The spelling of 31249993 in words is "thirty-one million, two hundred forty-nine thousand, nine hundred ninety-three".