1981863097 has 2 divisors, whose sum is σ = 1981863098. Its totient is φ = 1981863096.

The previous prime is 1981863073. The next prime is 1981863109. The reversal of 1981863097 is 7903681891.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1160696761 + 821166336 = 34069^2 + 28656^2 .

It is a cyclic number.

It is not a de Polignac number, because 1981863097 - 2¹⁵ = 1981830329 is a prime.

It is not a weakly prime, because it can be changed into another prime (1981863497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 990931548 + 990931549.

It is an arithmetic number, because the mean of its divisors is an integer number (990931549).

Almost surely, 2^1981863097 is an apocalyptic number.

It is an amenable number.

1981863097 is a deficient number, since it is larger than the sum of its proper divisors (1).

1981863097 is an equidigital number, since it uses as much as digits as its factorization.

1981863097 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 653184, while the sum is 52.

The square root of 1981863097 is about 44518.1209958372. The cubic root of 1981863097 is about 1256.1009681313.

The spelling of 1981863097 in words is "one billion, nine hundred eighty-one million, eight hundred sixty-three thousand, ninety-seven".