31386749 has 2 divisors, whose sum is σ = 31386750. Its totient is φ = 31386748.

The previous prime is 31386739. The next prime is 31386781. The reversal of 31386749 is 94768313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19518724 + 11868025 = 4418^2 + 3445^2 .

It is a cyclic number.

It is not a de Polignac number, because 31386749 - 2¹² = 31382653 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31386739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15693374 + 15693375.

It is an arithmetic number, because the mean of its divisors is an integer number (15693375).

Almost surely, 2^31386749 is an apocalyptic number.

It is an amenable number.

31386749 is a deficient number, since it is larger than the sum of its proper divisors (1).

31386749 is an equidigital number, since it uses as much as digits as its factorization.

31386749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108864, while the sum is 41.

The square root of 31386749 is about 5602.3877945033. The cubic root of 31386749 is about 315.4390417716.

The spelling of 31386749 in words is "thirty-one million, three hundred eighty-six thousand, seven hundred forty-nine".