991991353005 has 12 divisors (see below), whose sum is σ = 1719451678620. Its totient is φ = 529062054912.

The previous prime is 991991352949. The next prime is 991991353081. The reversal of 991991353005 is 500353199199.

991991353005 is a `hidden beast` number, since 9 + 9 + 1 + 99 + 13 + 530 + 0 + 5 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 771344140644 + 220647212361 = 878262^2 + 469731^2 .

It is not a de Polignac number, because 991991353005 - 2¹⁴ = 991991336621 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11022126100 + ... + 11022126189.

It is an arithmetic number, because the mean of its divisors is an integer number (143287639885).

Almost surely, 2^991991353005 is an apocalyptic number.

It is an amenable number.

991991353005 is a deficient number, since it is larger than the sum of its proper divisors (727460325615).

991991353005 is a wasteful number, since it uses less digits than its factorization.

991991353005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22044252300 (or 22044252297 counting only the distinct ones).

The product of its (nonzero) digits is 1476225, while the sum is 54.

The spelling of 991991353005 in words is "nine hundred ninety-one billion, nine hundred ninety-one million, three hundred fifty-three thousand, five".