18919447995 has 32 divisors (see below), whose sum is σ = 34604140032. Its totient is φ = 8646746112.

The previous prime is 18919447973. The next prime is 18919448039. The reversal of 18919447995 is 59974491981.

It is a happy number.

It is not a de Polignac number, because 18919447995 - 2⁷ = 18919447867 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 450619 + ... + 490811.

It is an arithmetic number, because the mean of its divisors is an integer number (1081379376).

Almost surely, 2^18919447995 is an apocalyptic number.

18919447995 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

18919447995 is a deficient number, since it is larger than the sum of its proper divisors (15684692037).

18919447995 is a wasteful number, since it uses less digits than its factorization.

18919447995 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44691.

The product of its digits is 29393280, while the sum is 66.

The spelling of 18919447995 in words is "eighteen billion, nine hundred nineteen million, four hundred forty-seven thousand, nine hundred ninety-five".