18951987792 has 20 divisors (see below), whose sum is σ = 48959301920. Its totient is φ = 6317329248.

The previous prime is 18951987781. The next prime is 18951987799. The reversal of 18951987792 is 29778915981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18951987799) 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, 197416492 + ... + 197416587.

It is an arithmetic number, because the mean of its divisors is an integer number (2447965096).

Almost surely, 2^18951987792 is an apocalyptic number.

18951987792 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

18951987792 is an abundant number, since it is smaller than the sum of its proper divisors (30007314128).

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

18951987792 is a wasteful number, since it uses less digits than its factorization.

18951987792 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 394833090 (or 394833084 counting only the distinct ones).

The product of its digits is 22861440, while the sum is 66.

The spelling of 18951987792 in words is "eighteen billion, nine hundred fifty-one million, nine hundred eighty-seven thousand, seven hundred ninety-two".