31320571697 has 2 divisors, whose sum is σ = 31320571698. Its totient is φ = 31320571696.

The previous prime is 31320571693. The next prime is 31320571739. The reversal of 31320571697 is 79617502313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16437547681 + 14883024016 = 128209^2 + 121996^2 .

It is a cyclic number.

It is not a de Polignac number, because 31320571697 - 2² = 31320571693 is a prime.

It is a super-2 number, since 2×31320571697² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31320571693) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15660285848 + 15660285849.

It is an arithmetic number, because the mean of its divisors is an integer number (15660285849).

Almost surely, 2^31320571697 is an apocalyptic number.

It is an amenable number.

31320571697 is a deficient number, since it is larger than the sum of its proper divisors (1).

31320571697 is an equidigital number, since it uses as much as digits as its factorization.

31320571697 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 238140, while the sum is 44.

The spelling of 31320571697 in words is "thirty-one billion, three hundred twenty million, five hundred seventy-one thousand, six hundred ninety-seven".