21214642216 has 8 divisors (see below), whose sum is σ = 39777454170. Its totient is φ = 10607321104.

The previous prime is 21214642199. The next prime is 21214642271. The reversal of 21214642216 is 61224641212.

It can be written as a sum of positive squares in only one way, i.e., 15537622500 + 5677019716 = 124650^2 + 75346^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×21214642216² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1325915131 + ... + 1325915146.

Almost surely, 2^21214642216 is an apocalyptic number.

It is an amenable number.

21214642216 is a deficient number, since it is larger than the sum of its proper divisors (18562811954).

21214642216 is a wasteful number, since it uses less digits than its factorization.

21214642216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2651830283 (or 2651830279 counting only the distinct ones).

The product of its digits is 9216, while the sum is 31.

The spelling of 21214642216 in words is "twenty-one billion, two hundred fourteen million, six hundred forty-two thousand, two hundred sixteen".