1920000020191 has 4 divisors (see below), whose sum is σ = 2094545476584. Its totient is φ = 1745454563800.

The previous prime is 1920000020161. The next prime is 1920000020231. The reversal of 1920000020191 is 1910200000291.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1920000020191 - 2²³ = 1919991631583 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1920000020111) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 87272728180 + ... + 87272728201.

It is an arithmetic number, because the mean of its divisors is an integer number (523636369146).

Almost surely, 2^{1920000020191} is an apocalyptic number.

1920000020191 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1920000020191 is a deficient number, since it is larger than the sum of its proper divisors (174545456393).

1920000020191 is a wasteful number, since it uses less digits than its factorization.

1920000020191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174545456392.

The product of its (nonzero) digits is 324, while the sum is 25.

The spelling of 1920000020191 in words is "one trillion, nine hundred twenty billion, twenty thousand, one hundred ninety-one".