791656981 has 2 divisors, whose sum is σ = 791656982. Its totient is φ = 791656980.

The previous prime is 791656979. The next prime is 791656997. The reversal of 791656981 is 189656197.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 431226756 + 360430225 = 20766^2 + 18985^2 .

It is a cyclic number.

It is not a de Polignac number, because 791656981 - 2¹ = 791656979 is a prime.

It is a super-2 number, since 2×791656981² = 1253441551132068722, which contains 22 as substring.

Together with 791656979, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (791656381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 395828490 + 395828491.

It is an arithmetic number, because the mean of its divisors is an integer number (395828491).

Almost surely, 2^791656981 is an apocalyptic number.

It is an amenable number.

791656981 is a deficient number, since it is larger than the sum of its proper divisors (1).

791656981 is an equidigital number, since it uses as much as digits as its factorization.

791656981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 816480, while the sum is 52.

The square root of 791656981 is about 28136.3995742170. The cubic root of 791656981 is about 925.0794111517.

The spelling of 791656981 in words is "seven hundred ninety-one million, six hundred fifty-six thousand, nine hundred eighty-one".