216696881 has 4 divisors (see below), whose sum is σ = 228102000. Its totient is φ = 205291764.

The previous prime is 216696877. The next prime is 216696937. The reversal of 216696881 is 188696612.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 216696881 - 2² = 216696877 is a prime.

It is a super-2 number, since 2×216696881² = 93915076470256322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216696481) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5702531 + ... + 5702568.

It is an arithmetic number, because the mean of its divisors is an integer number (57025500).

Almost surely, 2^216696881 is an apocalyptic number.

It is an amenable number.

216696881 is a deficient number, since it is larger than the sum of its proper divisors (11405119).

216696881 is a wasteful number, since it uses less digits than its factorization.

216696881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11405118.

The product of its digits is 248832, while the sum is 47.

The square root of 216696881 is about 14720.6277379737. The cubic root of 216696881 is about 600.6445674918.

The spelling of 216696881 in words is "two hundred sixteen million, six hundred ninety-six thousand, eight hundred eighty-one".