216721706706 has 40 divisors (see below), whose sum is σ = 486367960320. Its totient is φ = 72128879352.

The previous prime is 216721706693. The next prime is 216721706711. The reversal of 216721706706 is 607607127612.

It is a super-2 number, since 2×216721706706² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 929026 + ... + 1138653.

It is an arithmetic number, because the mean of its divisors is an integer number (12159199008).

Almost surely, 2^216721706706 is an apocalyptic number.

216721706706 is an abundant number, since it is smaller than the sum of its proper divisors (269646253614).

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

216721706706 is a wasteful number, since it uses less digits than its factorization.

216721706706 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2068340 (or 2068331 counting only the distinct ones).

The product of its (nonzero) digits is 296352, while the sum is 45.

The spelling of 216721706706 in words is "two hundred sixteen billion, seven hundred twenty-one million, seven hundred six thousand, seven hundred six".