21628351206 has 384 divisors, whose sum is σ = 64408780800. Its totient is φ = 5075239680.

The previous prime is 21628351181. The next prime is 21628351229. The reversal of 21628351206 is 60215382612.

21628351206 is a `hidden beast` number, since 2 + 1 + 62 + 83 + 512 + 0 + 6 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 96988011 + ... + 96988233.

It is an arithmetic number, because the mean of its divisors is an integer number (167731200).

Almost surely, 2^21628351206 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21628351206, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32204390400).

21628351206 is an abundant number, since it is smaller than the sum of its proper divisors (42780429594).

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

21628351206 is a wasteful number, since it uses less digits than its factorization.

21628351206 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 424 (or 421 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The spelling of 21628351206 in words is "twenty-one billion, six hundred twenty-eight million, three hundred fifty-one thousand, two hundred six".