21116166661612 has 12 divisors (see below), whose sum is σ = 40312681808616. Its totient is φ = 9598257573440.

The previous prime is 21116166661561. The next prime is 21116166661637. The reversal of 21116166661612 is 21616666161112.

It is a happy 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, 239956439293 + ... + 239956439380.

It is an arithmetic number, because the mean of its divisors is an integer number (3359390150718).

Almost surely, 2^{21116166661612} is an apocalyptic number.

21116166661612 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21116166661612 is a deficient number, since it is larger than the sum of its proper divisors (19196515147004).

21116166661612 is a wasteful number, since it uses less digits than its factorization.

21116166661612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 479912878688 (or 479912878686 counting only the distinct ones).

The product of its digits is 186624, while the sum is 46.

The spelling of 21116166661612 in words is "twenty-one trillion, one hundred sixteen billion, one hundred sixty-six million, six hundred sixty-one thousand, six hundred twelve".