31201312691 has 2 divisors, whose sum is σ = 31201312692. Its totient is φ = 31201312690.

The previous prime is 31201312633. The next prime is 31201312697. The reversal of 31201312691 is 19621310213.

It is a strong prime.

It is an emirp because it is prime and its reverse (19621310213) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31201312691 - 2¹⁰ = 31201311667 is a prime.

It is a super-2 number, since 2×31201312691² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31201312697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15600656345 + 15600656346.

It is an arithmetic number, because the mean of its divisors is an integer number (15600656346).

Almost surely, 2^31201312691 is an apocalyptic number.

31201312691 is a deficient number, since it is larger than the sum of its proper divisors (1).

31201312691 is an equidigital number, since it uses as much as digits as its factorization.

31201312691 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 29.

The spelling of 31201312691 in words is "thirty-one billion, two hundred one million, three hundred twelve thousand, six hundred ninety-one".