31857504661 has 2 divisors, whose sum is σ = 31857504662. Its totient is φ = 31857504660.

The previous prime is 31857504571. The next prime is 31857504683. The reversal of 31857504661 is 16640575813.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30939051025 + 918453636 = 175895^2 + 30306^2 .

It is an emirp because it is prime and its reverse (16640575813) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31857504661 - 2¹¹ = 31857502613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31857504691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15928752330 + 15928752331.

It is an arithmetic number, because the mean of its divisors is an integer number (15928752331).

Almost surely, 2^31857504661 is an apocalyptic number.

It is an amenable number.

31857504661 is a deficient number, since it is larger than the sum of its proper divisors (1).

31857504661 is an equidigital number, since it uses as much as digits as its factorization.

31857504661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 604800, while the sum is 46.

The spelling of 31857504661 in words is "thirty-one billion, eight hundred fifty-seven million, five hundred four thousand, six hundred sixty-one".