2261161997 has 2 divisors, whose sum is σ = 2261161998. Its totient is φ = 2261161996.

The previous prime is 2261161927. The next prime is 2261162069. The reversal of 2261161997 is 7991611622.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2038883716 + 222278281 = 45154^2 + 14909^2 .

It is a cyclic number.

It is not a de Polignac number, because 2261161997 - 2²⁰ = 2260113421 is a prime.

It is a super-2 number, since 2×2261161997² = 10225707153354056018, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2261161907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1130580998 + 1130580999.

It is an arithmetic number, because the mean of its divisors is an integer number (1130580999).

Almost surely, 2^2261161997 is an apocalyptic number.

It is an amenable number.

2261161997 is a deficient number, since it is larger than the sum of its proper divisors (1).

2261161997 is an equidigital number, since it uses as much as digits as its factorization.

2261161997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 81648, while the sum is 44.

The square root of 2261161997 is about 47551.6771207914. The cubic root of 2261161997 is about 1312.5339909806.

The spelling of 2261161997 in words is "two billion, two hundred sixty-one million, one hundred sixty-one thousand, nine hundred ninety-seven".