31149397 has 2 divisors, whose sum is σ = 31149398. Its totient is φ = 31149396.

The previous prime is 31149373. The next prime is 31149403. The reversal of 31149397 is 79394113.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30924721 + 224676 = 5561^2 + 474^2 .

It is an emirp because it is prime and its reverse (79394113) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31149397 - 2⁷ = 31149269 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31149317) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15574698 + 15574699.

It is an arithmetic number, because the mean of its divisors is an integer number (15574699).

Almost surely, 2^31149397 is an apocalyptic number.

It is an amenable number.

31149397 is a deficient number, since it is larger than the sum of its proper divisors (1).

31149397 is an equidigital number, since it uses as much as digits as its factorization.

31149397 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20412, while the sum is 37.

The square root of 31149397 is about 5581.1644842273. The cubic root of 31149397 is about 314.6418942113.

The spelling of 31149397 in words is "thirty-one million, one hundred forty-nine thousand, three hundred ninety-seven".