1219287161 has 2 divisors, whose sum is σ = 1219287162. Its totient is φ = 1219287160.

The previous prime is 1219287127. The next prime is 1219287169. The reversal of 1219287161 is 1617829121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 711235561 + 508051600 = 26669^2 + 22540^2 .

It is a cyclic number.

It is not a de Polignac number, because 1219287161 - 2¹⁰ = 1219286137 is a prime.

It is a super-2 number, since 2×1219287161² = 2973322361958879842, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1219287169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 609643580 + 609643581.

It is an arithmetic number, because the mean of its divisors is an integer number (609643581).

Almost surely, 2^1219287161 is an apocalyptic number.

It is an amenable number.

1219287161 is a deficient number, since it is larger than the sum of its proper divisors (1).

1219287161 is an equidigital number, since it uses as much as digits as its factorization.

1219287161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096, while the sum is 38.

The square root of 1219287161 is about 34918.2926415368. The cubic root of 1219287161 is about 1068.3215776727.

The spelling of 1219287161 in words is "one billion, two hundred nineteen million, two hundred eighty-seven thousand, one hundred sixty-one".