1577221442161 has 2 divisors, whose sum is σ = 1577221442162. Its totient is φ = 1577221442160.

The previous prime is 1577221442119. The next prime is 1577221442171. The reversal of 1577221442161 is 1612441227751.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1573569536400 + 3651905761 = 1254420^2 + 60431^2 .

It is a cyclic number.

It is not a de Polignac number, because 1577221442161 - 2¹⁹ = 1577220917873 is a prime.

It is a super-2 number, since 2×1577221442161² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1577221442171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 788610721080 + 788610721081.

It is an arithmetic number, because the mean of its divisors is an integer number (788610721081).

Almost surely, 2^{1577221442161} is an apocalyptic number.

It is an amenable number.

1577221442161 is a deficient number, since it is larger than the sum of its proper divisors (1).

1577221442161 is an equidigital number, since it uses as much as digits as its factorization.

1577221442161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 188160, while the sum is 43.

The spelling of 1577221442161 in words is "one trillion, five hundred seventy-seven billion, two hundred twenty-one million, four hundred forty-two thousand, one hundred sixty-one".