331988121761 has 2 divisors, whose sum is σ = 331988121762. Its totient is φ = 331988121760.

The previous prime is 331988121739. The next prime is 331988121767. The reversal of 331988121761 is 167121889133.

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., 309073731136 + 22914390625 = 555944^2 + 151375^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-331988121761 is a prime.

It is a super-2 number, since 2×331988121761² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (331988121767) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165994060880 + 165994060881.

It is an arithmetic number, because the mean of its divisors is an integer number (165994060881).

Almost surely, 2^331988121761 is an apocalyptic number.

It is an amenable number.

331988121761 is a deficient number, since it is larger than the sum of its proper divisors (1).

331988121761 is an equidigital number, since it uses as much as digits as its factorization.

331988121761 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 435456, while the sum is 50.

The spelling of 331988121761 in words is "three hundred thirty-one billion, nine hundred eighty-eight million, one hundred twenty-one thousand, seven hundred sixty-one".