1991141812 has 24 divisors (see below), whose sum is σ = 3834919872. Its totient is φ = 897052800.

The previous prime is 1991141807. The next prime is 1991141819. The reversal of 1991141812 is 2181411991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1991141819) 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, 195264 + ... + 205207.

It is an arithmetic number, because the mean of its divisors is an integer number (159788328).

Almost surely, 2^1991141812 is an apocalyptic number.

It is an amenable number.

1991141812 is a deficient number, since it is larger than the sum of its proper divisors (1843778060).

1991141812 is a wasteful number, since it uses less digits than its factorization.

1991141812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 400599 (or 400597 counting only the distinct ones).

The product of its digits is 5184, while the sum is 37.

The square root of 1991141812 is about 44622.2120921857. The cubic root of 1991141812 is about 1258.0581940065.

The spelling of 1991141812 in words is "one billion, nine hundred ninety-one million, one hundred forty-one thousand, eight hundred twelve".