18777834649 has 8 divisors (see below), whose sum is σ = 21470701760. Its totient is φ = 16087547376.

The previous prime is 18777834643. The next prime is 18777834697. The reversal of 18777834649 is 94643877781.

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

It is a cyclic number.

It is not a de Polignac number, because 18777834649 - 2³ = 18777834641 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18777834641) 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, 629334 + ... + 658495.

It is an arithmetic number, because the mean of its divisors is an integer number (2683837720).

Almost surely, 2^18777834649 is an apocalyptic number.

It is an amenable number.

18777834649 is a deficient number, since it is larger than the sum of its proper divisors (2692867111).

18777834649 is a wasteful number, since it uses less digits than its factorization.

18777834649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1289919.

The product of its digits is 56899584, while the sum is 64.

The spelling of 18777834649 in words is "eighteen billion, seven hundred seventy-seven million, eight hundred thirty-four thousand, six hundred forty-nine".