19791805140 has 48 divisors (see below), whose sum is σ = 61574506560. Its totient is φ = 5277814560.

The previous prime is 19791805051. The next prime is 19791805151. The reversal of 19791805140 is 4150819791.

It is a happy number.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18325206 + ... + 18326285.

It is an arithmetic number, because the mean of its divisors is an integer number (1282802220).

Almost surely, 2^19791805140 is an apocalyptic number.

19791805140 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19791805140 is an abundant number, since it is smaller than the sum of its proper divisors (41782701420).

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

19791805140 is a wasteful number, since it uses less digits than its factorization.

19791805140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36651509 (or 36651501 counting only the distinct ones).

The product of its (nonzero) digits is 90720, while the sum is 45.

The spelling of 19791805140 in words is "nineteen billion, seven hundred ninety-one million, eight hundred five thousand, one hundred forty".