991967659 has 2 divisors, whose sum is σ = 991967660. Its totient is φ = 991967658.

The previous prime is 991967617. The next prime is 991967671. The reversal of 991967659 is 956769199.

991967659 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 is a cyclic number.

It is not a de Polignac number, because 991967659 - 2²¹ = 989870507 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 991967597 and 991967606.

It is not a weakly prime, because it can be changed into another prime (991967609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495983829 + 495983830.

It is an arithmetic number, because the mean of its divisors is an integer number (495983830).

Almost surely, 2^991967659 is an apocalyptic number.

991967659 is a deficient number, since it is larger than the sum of its proper divisors (1).

991967659 is an equidigital number, since it uses as much as digits as its factorization.

991967659 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8266860, while the sum is 61.

The square root of 991967659 is about 31495.5180779742. The cubic root of 991967659 is about 997.3153521155.

The spelling of 991967659 in words is "nine hundred ninety-one million, nine hundred sixty-seven thousand, six hundred fifty-nine".