1197390681 has 20 divisors (see below), whose sum is σ = 1822450212. Its totient is φ = 783196128.

The previous prime is 1197390679. The next prime is 1197390713. The reversal of 1197390681 is 1860937911.

It can be written as a sum of positive squares in 2 ways, for example, as 357550281 + 839840400 = 18909^2 + 28980^2 .

It is not a de Polignac number, because 1197390681 - 2¹ = 1197390679 is a prime.

It is a super-2 number, since 2×1197390681² = 2867488885891287522, which contains 22 as substring.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (1197390611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 135166 + ... + 143751.

Almost surely, 2^1197390681 is an apocalyptic number.

It is an amenable number.

1197390681 is a deficient number, since it is larger than the sum of its proper divisors (625059531).

1197390681 is an equidigital number, since it uses as much as digits as its factorization.

1197390681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 278982 (or 278973 counting only the distinct ones).

The product of its (nonzero) digits is 81648, while the sum is 45.

The square root of 1197390681 is about 34603.3333798928. Note that the first 4 decimals coincide. The cubic root of 1197390681 is about 1061.8877837957.

The spelling of 1197390681 in words is "one billion, one hundred ninety-seven million, three hundred ninety thousand, six hundred eighty-one".