1991314969 has 20 divisors (see below), whose sum is σ = 2445385040. Its totient is φ = 1616970600.

The previous prime is 1991314967. The next prime is 1991314979. The reversal of 1991314969 is 9694131991.

It is not a de Polignac number, because 1991314969 - 2¹ = 1991314967 is a prime.

It is a super-2 number, since 2×1991314969² = 7930670611526941922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1991314961) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 23794 + ... + 67444.

It is an arithmetic number, because the mean of its divisors is an integer number (122269252).

Almost surely, 2^1991314969 is an apocalyptic number.

1991314969 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

1991314969 is a deficient number, since it is larger than the sum of its proper divisors (454070071).

1991314969 is an frugal number, since it uses more digits than its factorization.

1991314969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43698 (or 43677 counting only the distinct ones).

The product of its digits is 472392, while the sum is 52.

The square root of 1991314969 is about 44624.1523056741. The cubic root of 1991314969 is about 1258.0946614020.

The spelling of 1991314969 in words is "one billion, nine hundred ninety-one million, three hundred fourteen thousand, nine hundred sixty-nine".