21116351663868 has 24 divisors (see below), whose sum is σ = 49338706181968. Its totient is φ = 7029181178496.

The previous prime is 21116351663801. The next prime is 21116351663879. The reversal of 21116351663868 is 86836615361112.

It is a Smith number, since the sum of its digits (57) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1200329521 + ... + 1200347112.

Almost surely, 2^{21116351663868} is an apocalyptic number.

It is an amenable number.

21116351663868 is an abundant number, since it is smaller than the sum of its proper divisors (28222354518100).

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

21116351663868 is a wasteful number, since it uses less digits than its factorization.

21116351663868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2400677373 (or 2400677371 counting only the distinct ones).

The product of its digits is 7464960, while the sum is 57.

The spelling of 21116351663868 in words is "twenty-one trillion, one hundred sixteen billion, three hundred fifty-one million, six hundred sixty-three thousand, eight hundred sixty-eight".