1091647993 has 2 divisors, whose sum is σ = 1091647994. Its totient is φ = 1091647992.

The previous prime is 1091647961. The next prime is 1091648017. The reversal of 1091647993 is 3997461901.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 939545104 + 152102889 = 30652^2 + 12333^2 .

It is a cyclic number.

It is not a de Polignac number, because 1091647993 - 2⁵ = 1091647961 is a prime.

It is not a weakly prime, because it can be changed into another prime (1091647093) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 545823996 + 545823997.

It is an arithmetic number, because the mean of its divisors is an integer number (545823997).

Almost surely, 2^1091647993 is an apocalyptic number.

It is an amenable number.

1091647993 is a deficient number, since it is larger than the sum of its proper divisors (1).

1091647993 is an equidigital number, since it uses as much as digits as its factorization.

1091647993 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 367416, while the sum is 49.

The square root of 1091647993 is about 33040.0967462264. The cubic root of 1091647993 is about 1029.6608658221.

The spelling of 1091647993 in words is "one billion, ninety-one million, six hundred forty-seven thousand, nine hundred ninety-three".