21774424320 has 864 divisors, whose sum is σ = 87688581120. Its totient is φ = 5109350400.

The previous prime is 21774424319. The next prime is 21774424339. The reversal of 21774424320 is 2342447712.

21774424320 is a `hidden beast` number, since 2 + 177 + 442 + 43 + 2 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (864).

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

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 171452097 + ... + 171452223.

Almost surely, 2^21774424320 is an apocalyptic number.

21774424320 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 21774424320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43844290560).

21774424320 is an abundant number, since it is smaller than the sum of its proper divisors (65914156800).

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

21774424320 is a wasteful number, since it uses less digits than its factorization.

21774424320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220 (or 189 counting only the distinct ones).

The product of its (nonzero) digits is 75264, while the sum is 36.

It can be divided in two parts, 217744 and 24320, that added together give a square (242064 = 492²).

The spelling of 21774424320 in words is "twenty-one billion, seven hundred seventy-four million, four hundred twenty-four thousand, three hundred twenty".