918191909969 has 2 divisors, whose sum is σ = 918191909970. Its totient is φ = 918191909968.

The previous prime is 918191909951. The next prime is 918191910047. The reversal of 918191909969 is 969909191819.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 907932651025 + 10259258944 = 952855^2 + 101288^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-918191909969 is a prime.

It is a super-2 number, since 2×918191909969² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (918191909669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 459095954984 + 459095954985.

It is an arithmetic number, because the mean of its divisors is an integer number (459095954985).

Almost surely, 2^918191909969 is an apocalyptic number.

It is an amenable number.

918191909969 is a deficient number, since it is larger than the sum of its proper divisors (1).

918191909969 is an equidigital number, since it uses as much as digits as its factorization.

918191909969 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25509168, while the sum is 71.

The spelling of 918191909969 in words is "nine hundred eighteen billion, one hundred ninety-one million, nine hundred nine thousand, nine hundred sixty-nine".