216693321816 has 16 divisors (see below), whose sum is σ = 541733304600. Its totient is φ = 72231107264.

The previous prime is 216693321809. The next prime is 216693321827. The reversal of 216693321816 is 618123396612.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4514444181 + ... + 4514444228.

Almost surely, 2^216693321816 is an apocalyptic number.

It is an amenable number.

216693321816 is an abundant number, since it is smaller than the sum of its proper divisors (325039982784).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

216693321816 is a wasteful number, since it uses less digits than its factorization.

216693321816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9028888418 (or 9028888414 counting only the distinct ones).

The product of its digits is 559872, while the sum is 48.

The spelling of 216693321816 in words is "two hundred sixteen billion, six hundred ninety-three million, three hundred twenty-one thousand, eight hundred sixteen".