18720146887 has 8 divisors (see below), whose sum is σ = 21346050096. Its totient is φ = 16263656832.

The previous prime is 18720146873. The next prime is 18720146923. The reversal of 18720146887 is 78864102781.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-18720146887 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18720146807) 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, 42353053 + ... + 42353494.

It is an arithmetic number, because the mean of its divisors is an integer number (2668256262).

Almost surely, 2^18720146887 is an apocalyptic number.

18720146887 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

18720146887 is a deficient number, since it is larger than the sum of its proper divisors (2625903209).

18720146887 is a wasteful number, since it uses less digits than its factorization.

18720146887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84706577.

The product of its (nonzero) digits is 1204224, while the sum is 52.

The spelling of 18720146887 in words is "eighteen billion, seven hundred twenty million, one hundred forty-six thousand, eight hundred eighty-seven".