21189723384 has 64 divisors (see below), whose sum is σ = 54709079040. Its totient is φ = 6832154880.

The previous prime is 21189723377. The next prime is 21189723407. The reversal of 21189723384 is 48332798112.

It is a happy number.

It is a super-2 number, since 2×21189723384² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1941607 + ... + 1952489.

It is an arithmetic number, because the mean of its divisors is an integer number (854829360).

Almost surely, 2^21189723384 is an apocalyptic number.

21189723384 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21189723384 is an abundant number, since it is smaller than the sum of its proper divisors (33519355656).

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

21189723384 is a wasteful number, since it uses less digits than its factorization.

21189723384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13540 (or 13536 counting only the distinct ones).

The product of its digits is 580608, while the sum is 48.

The spelling of 21189723384 in words is "twenty-one billion, one hundred eighty-nine million, seven hundred twenty-three thousand, three hundred eighty-four".