21427613280 has 576 divisors, whose sum is σ = 85083747840. Its totient is φ = 4870914048.

The previous prime is 21427613243. The next prime is 21427613329. The reversal of 21427613280 is 8231672412.

It is a happy number.

21427613280 is a `hidden beast` number, since 2 + 14 + 2 + 7 + 613 + 28 + 0 = 666.

It is a super-2 number, since 2×21427613280² (a number of 21 digits) contains 22 as substring.

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

It is a congruent number.

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, 10696759 + ... + 10698761.

It is an arithmetic number, because the mean of its divisors is an integer number (147714840).

Almost surely, 2^21427613280 is an apocalyptic number.

21427613280 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 21427613280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42541873920).

21427613280 is an abundant number, since it is smaller than the sum of its proper divisors (63656134560).

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

21427613280 is a wasteful number, since it uses less digits than its factorization.

21427613280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2083 (or 2072 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The spelling of 21427613280 in words is "twenty-one billion, four hundred twenty-seven million, six hundred thirteen thousand, two hundred eighty".