21194646984 has 288 divisors, whose sum is σ = 72718776000. Its totient is φ = 5538564864.

The previous prime is 21194646973. The next prime is 21194647037. The reversal of 21194646984 is 48964649112.

21194646984 is a `hidden beast` number, since 2 + 11 + 94 + 6 + 469 + 84 = 666.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21194646984.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1938477 + ... + 1949379.

It is an arithmetic number, because the mean of its divisors is an integer number (252495750).

Almost surely, 2^21194646984 is an apocalyptic number.

21194646984 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21194646984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36359388000).

21194646984 is an abundant number, since it is smaller than the sum of its proper divisors (51524129016).

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

21194646984 is a wasteful number, since it uses less digits than its factorization.

21194646984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10977 (or 10963 counting only the distinct ones).

The product of its digits is 2985984, while the sum is 54.

The spelling of 21194646984 in words is "twenty-one billion, one hundred ninety-four million, six hundred forty-six thousand, nine hundred eighty-four".