1997161 has 2 divisors, whose sum is σ = 1997162. Its totient is φ = 1997160.

The previous prime is 1997141. The next prime is 1997173. The reversal of 1997161 is 1617991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1907161 + 90000 = 1381^2 + 300^2 .

It is a cyclic number.

It is not a de Polignac number, because 1997161 - 2⁵ = 1997129 is a prime.

It is not a weakly prime, because it can be changed into another prime (1997101) 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, 998580 + 998581.

It is an arithmetic number, because the mean of its divisors is an integer number (998581).

2^1997161 is an apocalyptic number.

It is an amenable number.

1997161 is a deficient number, since it is larger than the sum of its proper divisors (1).

1997161 is an equidigital number, since it uses as much as digits as its factorization.

1997161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3402, while the sum is 34.

The square root of 1997161 is about 1413.2094678426. The cubic root of 1997161 is about 125.9324614949.

The spelling of 1997161 in words is "one million, nine hundred ninety-seven thousand, one hundred sixty-one".