21678762168 has 96 divisors (see below), whose sum is σ = 71048072160. Its totient is φ = 5829580800.

The previous prime is 21678762143. The next prime is 21678762187. The reversal of 21678762168 is 86126787612.

21678762168 is a `hidden beast` number, since 2 + 1 + 6 + 7 + 8 + 7 + 621 + 6 + 8 = 666.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1256533 + ... + 1273668.

It is an arithmetic number, because the mean of its divisors is an integer number (740084085).

Almost surely, 2^21678762168 is an apocalyptic number.

21678762168 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21678762168 is an abundant number, since it is smaller than the sum of its proper divisors (49369309992).

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

21678762168 is a wasteful number, since it uses less digits than its factorization.

21678762168 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2530237 (or 2530230 counting only the distinct ones).

The product of its digits is 2709504, while the sum is 54.

The spelling of 21678762168 in words is "twenty-one billion, six hundred seventy-eight million, seven hundred sixty-two thousand, one hundred sixty-eight".