816816919977 has 12 divisors (see below), whose sum is σ = 1191301485504. Its totient is φ = 539257771800.

The previous prime is 816816919973. The next prime is 816816919979. The reversal of 816816919977 is 779919618618.

816816919977 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 816816919977 - 2² = 816816919973 is a prime.

It is not an unprimeable number, because it can be changed into a prime (816816919973) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 440569149 + ... + 440571002.

It is an arithmetic number, because the mean of its divisors is an integer number (99275123792).

Almost surely, 2^816816919977 is an apocalyptic number.

It is an amenable number.

816816919977 is a deficient number, since it is larger than the sum of its proper divisors (374484565527).

816816919977 is a wasteful number, since it uses less digits than its factorization.

816816919977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 881140260 (or 881140257 counting only the distinct ones).

The product of its digits is 82301184, while the sum is 72.

The spelling of 816816919977 in words is "eight hundred sixteen billion, eight hundred sixteen million, nine hundred nineteen thousand, nine hundred seventy-seven".