2122198756921 has 2 divisors, whose sum is σ = 2122198756922. Its totient is φ = 2122198756920.

The previous prime is 2122198756901. The next prime is 2122198756939. The reversal of 2122198756921 is 1296578912212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2082653059600 + 39545697321 = 1443140^2 + 198861^2 .

It is a cyclic number.

It is not a de Polignac number, because 2122198756921 - 2⁷ = 2122198756793 is a prime.

It is not a weakly prime, because it can be changed into another prime (2122198756901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1061099378460 + 1061099378461.

It is an arithmetic number, because the mean of its divisors is an integer number (1061099378461).

Almost surely, 2^{2122198756921} is an apocalyptic number.

It is an amenable number.

2122198756921 is a deficient number, since it is larger than the sum of its proper divisors (1).

2122198756921 is an equidigital number, since it uses as much as digits as its factorization.

2122198756921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2177280, while the sum is 55.

The spelling of 2122198756921 in words is "two trillion, one hundred twenty-two billion, one hundred ninety-eight million, seven hundred fifty-six thousand, nine hundred twenty-one".