1791642217 has 2 divisors, whose sum is σ = 1791642218. Its totient is φ = 1791642216.

The previous prime is 1791642197. The next prime is 1791642287. The reversal of 1791642217 is 7122461971.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1668232336 + 123409881 = 40844^2 + 11109^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1791642217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1791642217.

It is not a weakly prime, because it can be changed into another prime (1791642287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 895821108 + 895821109.

It is an arithmetic number, because the mean of its divisors is an integer number (895821109).

Almost surely, 2^1791642217 is an apocalyptic number.

It is an amenable number.

1791642217 is a deficient number, since it is larger than the sum of its proper divisors (1).

1791642217 is an equidigital number, since it uses as much as digits as its factorization.

1791642217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 42336, while the sum is 40.

The square root of 1791642217 is about 42327.7948516102. The cubic root of 1791642217 is about 1214.5547470669.

The spelling of 1791642217 in words is "one billion, seven hundred ninety-one million, six hundred forty-two thousand, two hundred seventeen".