1991119228170 has 64 divisors (see below), whose sum is σ = 4960937128320. Its totient is φ = 510844416768.

The previous prime is 1991119228127. The next prime is 1991119228183. The reversal of 1991119228170 is 718229111991.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3797329 + ... + 4289748.

It is an arithmetic number, because the mean of its divisors is an integer number (77514642630).

Almost surely, 2^{1991119228170} is an apocalyptic number.

1991119228170 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1991119228170 is an abundant number, since it is smaller than the sum of its proper divisors (2969817900150).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1991119228170 is a wasteful number, since it uses less digits than its factorization.

1991119228170 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8087399.

The product of its (nonzero) digits is 163296, while the sum is 51.

The spelling of 1991119228170 in words is "one trillion, nine hundred ninety-one billion, one hundred nineteen million, two hundred twenty-eight thousand, one hundred seventy".