21616110612 has 18 divisors (see below), whose sum is σ = 54640724138. Its totient is φ = 7205370192.

The previous prime is 21616110611. The next prime is 21616110613. The reversal of 21616110612 is 21601161612.

21616110612 is a `hidden beast` number, since 21 + 6 + 16 + 1 + 10 + 612 = 666.

It is an interprime number because it is at equal distance from previous prime (21616110611) and next prime (21616110613).

It can be written as a sum of positive squares in only one way, i.e., 21268138896 + 347971716 = 145836^2 + 18654^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21616110611) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 300223723 + ... + 300223794.

Almost surely, 2^21616110612 is an apocalyptic number.

It is an amenable number.

21616110612 is an abundant number, since it is smaller than the sum of its proper divisors (33024613526).

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

21616110612 is a wasteful number, since it uses less digits than its factorization.

21616110612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 600447527 (or 600447522 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The spelling of 21616110612 in words is "twenty-one billion, six hundred sixteen million, one hundred ten thousand, six hundred twelve".