1247972681 has 2 divisors, whose sum is σ = 1247972682. Its totient is φ = 1247972680.

The previous prime is 1247972659. The next prime is 1247972707. The reversal of 1247972681 is 1862797421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 629207056 + 618765625 = 25084^2 + 24875^2 .

It is a cyclic number.

It is not a de Polignac number, because 1247972681 - 2²² = 1243778377 is a prime.

It is a super-2 number, since 2×1247972681² = 3114871625044655522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1247972641) 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, 623986340 + 623986341.

It is an arithmetic number, because the mean of its divisors is an integer number (623986341).

Almost surely, 2^1247972681 is an apocalyptic number.

It is an amenable number.

1247972681 is a deficient number, since it is larger than the sum of its proper divisors (1).

1247972681 is an equidigital number, since it uses as much as digits as its factorization.

1247972681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 338688, while the sum is 47.

The square root of 1247972681 is about 35326.6568047417. The cubic root of 1247972681 is about 1076.6346663780.

The spelling of 1247972681 in words is "one billion, two hundred forty-seven million, nine hundred seventy-two thousand, six hundred eighty-one".