991686445459 has 8 divisors (see below), whose sum is σ = 1011703592880. Its totient is φ = 971866511616.

The previous prime is 991686445433. The next prime is 991686445487. The reversal of 991686445459 is 954544686199.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 991686445459 - 2⁷ = 991686445331 is a prime.

It is a super-2 number, since 2×991686445459² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (991686445489) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49293237 + ... + 49313350.

It is an arithmetic number, because the mean of its divisors is an integer number (126462949110).

Almost surely, 2^991686445459 is an apocalyptic number.

991686445459 is a deficient number, since it is larger than the sum of its proper divisors (20017147421).

991686445459 is a wasteful number, since it uses less digits than its factorization.

991686445459 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98606789.

The product of its digits is 335923200, while the sum is 70.

The spelling of 991686445459 in words is "nine hundred ninety-one billion, six hundred eighty-six million, four hundred forty-five thousand, four hundred fifty-nine".