991099937 has 2 divisors, whose sum is σ = 991099938. Its totient is φ = 991099936.

The previous prime is 991099927. The next prime is 991099943. The reversal of 991099937 is 739990199.

It is a happy number.

991099937 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 631466641 + 359633296 = 25129^2 + 18964^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-991099937 is a prime.

It is a super-3 number, since 3×991099937³ (a number of 28 digits) contains 333 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (991099927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495549968 + 495549969.

It is an arithmetic number, because the mean of its divisors is an integer number (495549969).

Almost surely, 2^991099937 is an apocalyptic number.

It is an amenable number.

991099937 is a deficient number, since it is larger than the sum of its proper divisors (1).

991099937 is an equidigital number, since it uses as much as digits as its factorization.

991099937 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1240029, while the sum is 56.

The square root of 991099937 is about 31481.7397390932. The cubic root of 991099937 is about 997.0244673202.

The spelling of 991099937 in words is "nine hundred ninety-one million, ninety-nine thousand, nine hundred thirty-seven".