21324219840 has 1344 divisors, whose sum is σ = 100905868800. Its totient is φ = 4180377600.

The previous prime is 21324219823. The next prime is 21324219899. The reversal of 21324219840 is 4891242312.

It is a tau number, because it is divible by the number of its divisors (1344).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 21324219795 and 21324219804.

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, 88482120 + ... + 88482360.

Almost surely, 2^21324219840 is an apocalyptic number.

21324219840 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 21324219840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50452934400).

21324219840 is an abundant number, since it is smaller than the sum of its proper divisors (79581648960).

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

21324219840 is a wasteful number, since it uses less digits than its factorization.

21324219840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 311 (or 288 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The spelling of 21324219840 in words is "twenty-one billion, three hundred twenty-four million, two hundred nineteen thousand, eight hundred forty".