399617777666 has 32 divisors (see below), whose sum is σ = 668228123520. Its totient is φ = 178121376000.

The previous prime is 399617777641. The next prime is 399617777677. The reversal of 399617777666 is 666777716993.

It is a junction number, because it is equal to n+sod(n) for n = 399617777593 and 399617777602.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3234611 + ... + 3355881.

It is an arithmetic number, because the mean of its divisors is an integer number (20882128860).

Almost surely, 2^399617777666 is an apocalyptic number.

399617777666 is a deficient number, since it is larger than the sum of its proper divisors (268610345854).

399617777666 is a wasteful number, since it uses less digits than its factorization.

399617777666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126410.

The product of its digits is 756142128, while the sum is 74.

The spelling of 399617777666 in words is "three hundred ninety-nine billion, six hundred seventeen million, seven hundred seventy-seven thousand, six hundred sixty-six".