31347649 has 2 divisors, whose sum is σ = 31347650. Its totient is φ = 31347648.

The previous prime is 31347647. The next prime is 31347691. The reversal of 31347649 is 94674313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27615025 + 3732624 = 5255^2 + 1932^2 .

It is an emirp because it is prime and its reverse (94674313) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31347649 - 2¹ = 31347647 is a prime.

Together with 31347647, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (31347647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15673824 + 15673825.

It is an arithmetic number, because the mean of its divisors is an integer number (15673825).

Almost surely, 2^31347649 is an apocalyptic number.

It is an amenable number.

31347649 is a deficient number, since it is larger than the sum of its proper divisors (1).

31347649 is an equidigital number, since it uses as much as digits as its factorization.

31347649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54432, while the sum is 37.

The square root of 31347649 is about 5598.8971235414. The cubic root of 31347649 is about 315.3080014226.

The spelling of 31347649 in words is "thirty-one million, three hundred forty-seven thousand, six hundred forty-nine".