331977770221 has 2 divisors, whose sum is σ = 331977770222. Its totient is φ = 331977770220.

The previous prime is 331977770207. The next prime is 331977770233. The reversal of 331977770221 is 122077779133.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 314876977321 + 17100792900 = 561139^2 + 130770^2 .

It is an emirp because it is prime and its reverse (122077779133) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 331977770221 - 2⁹ = 331977769709 is a prime.

It is a super-2 number, since 2×331977770221² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (331977770281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165988885110 + 165988885111.

It is an arithmetic number, because the mean of its divisors is an integer number (165988885111).

Almost surely, 2^331977770221 is an apocalyptic number.

It is an amenable number.

331977770221 is a deficient number, since it is larger than the sum of its proper divisors (1).

331977770221 is an equidigital number, since it uses as much as digits as its factorization.

331977770221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 777924, while the sum is 49.

The spelling of 331977770221 in words is "three hundred thirty-one billion, nine hundred seventy-seven million, seven hundred seventy thousand, two hundred twenty-one".