9791561749 has 2 divisors, whose sum is σ = 9791561750. Its totient is φ = 9791561748.

The previous prime is 9791561743. The next prime is 9791561789. The reversal of 9791561749 is 9471651979.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9427439025 + 364122724 = 97095^2 + 19082^2 .

It is a cyclic number.

It is not a de Polignac number, because 9791561749 - 2²⁵ = 9758007317 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 9791561693 and 9791561702.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9791561743) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4895780874 + 4895780875.

It is an arithmetic number, because the mean of its divisors is an integer number (4895780875).

Almost surely, 2^9791561749 is an apocalyptic number.

It is an amenable number.

9791561749 is a deficient number, since it is larger than the sum of its proper divisors (1).

9791561749 is an equidigital number, since it uses as much as digits as its factorization.

9791561749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4286520, while the sum is 58.

The square root of 9791561749 is about 98952.3205842086. The cubic root of 9791561749 is about 2139.3605791180.

The spelling of 9791561749 in words is "nine billion, seven hundred ninety-one million, five hundred sixty-one thousand, seven hundred forty-nine".