21825780480 has 1440 divisors, whose sum is σ = 99364890240. Its totient is φ = 4459069440.

The previous prime is 21825780467. The next prime is 21825780481. The reversal of 21825780480 is 8408752812.

It is a happy number.

21825780480 is a `hidden beast` number, since 21 + 82 + 5 + 78 + 0 + 480 = 666.

It is a tau number, because it is divible by the number of its divisors (1440).

It is a super-2 number, since 2×21825780480² (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 not an unprimeable number, because it can be changed into a prime (21825780481) by changing a digit.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 357799650 + ... + 357799710.

It is an arithmetic number, because the mean of its divisors is an integer number (69003396).

Almost surely, 2^21825780480 is an apocalyptic number.

21825780480 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 21825780480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49682445120).

21825780480 is an abundant number, since it is smaller than the sum of its proper divisors (77539109760).

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

21825780480 is a wasteful number, since it uses less digits than its factorization.

21825780480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147 (or 124 counting only the distinct ones).

The product of its (nonzero) digits is 286720, while the sum is 45.

The spelling of 21825780480 in words is "twenty-one billion, eight hundred twenty-five million, seven hundred eighty thousand, four hundred eighty".