18731777449 has 16 divisors (see below), whose sum is σ = 23369794560. Its totient is φ = 14586258960.

The previous prime is 18731777447. The next prime is 18731777501. The reversal of 18731777449 is 94477713781.

It is not a de Polignac number, because 18731777449 - 2¹ = 18731777447 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 18731777393 and 18731777402.

It is not an unprimeable number, because it can be changed into a prime (18731777447) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32172 + ... + 196210.

It is an arithmetic number, because the mean of its divisors is an integer number (1460612160).

Almost surely, 2^18731777449 is an apocalyptic number.

It is an amenable number.

18731777449 is a deficient number, since it is larger than the sum of its proper divisors (4638017111).

18731777449 is a wasteful number, since it uses less digits than its factorization.

18731777449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165540.

The product of its digits is 8297856, while the sum is 58.

The spelling of 18731777449 in words is "eighteen billion, seven hundred thirty-one million, seven hundred seventy-seven thousand, four hundred forty-nine".