2279779197221 has 2 divisors, whose sum is σ = 2279779197222. Its totient is φ = 2279779197220.

The previous prime is 2279779197197. The next prime is 2279779197229. The reversal of 2279779197221 is 1227919779722.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2125341201025 + 154437996196 = 1457855^2 + 392986^2 .

It is a cyclic number.

It is not a de Polignac number, because 2279779197221 - 2¹⁴ = 2279779180837 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2279779197229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1139889598610 + 1139889598611.

It is an arithmetic number, because the mean of its divisors is an integer number (1139889598611).

Almost surely, 2^{2279779197221} is an apocalyptic number.

It is an amenable number.

2279779197221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2279779197221 is an equidigital number, since it uses as much as digits as its factorization.

2279779197221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 28005264, while the sum is 65.

The spelling of 2279779197221 in words is "two trillion, two hundred seventy-nine billion, seven hundred seventy-nine million, one hundred ninety-seven thousand, two hundred twenty-one".