21189854700 has 216 divisors, whose sum is σ = 78356096000. Its totient is φ = 4687113600.

The previous prime is 21189854681. The next prime is 21189854761. The reversal of 21189854700 is 745898112.

21189854700 is a `hidden beast` number, since 2 + 1 + 18 + 98 + 547 + 0 + 0 = 666.

It is a super-2 number, since 2×21189854700² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

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, 141051 + ... + 249549.

Almost surely, 2^21189854700 is an apocalyptic number.

21189854700 is a gapful number since it is divisible by the number (20) 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 21189854700, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39178048000).

21189854700 is an abundant number, since it is smaller than the sum of its proper divisors (57166241300).

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

21189854700 is a wasteful number, since it uses less digits than its factorization.

21189854700 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108557 (or 108547 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 45.

The spelling of 21189854700 in words is "twenty-one billion, one hundred eighty-nine million, eight hundred fifty-four thousand, seven hundred".