21976428240 has 960 divisors, whose sum is σ = 88914309120. Its totient is φ = 4817387520.

The previous prime is 21976428179. The next prime is 21976428269. The reversal of 21976428240 is 4282467912.

21976428240 is a `hidden beast` number, since 219 + 7 + 6 + 428 + 2 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 246926116 + ... + 246926204.

It is an arithmetic number, because the mean of its divisors is an integer number (92619072).

Almost surely, 2^21976428240 is an apocalyptic number.

21976428240 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 21976428240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44457154560).

21976428240 is an abundant number, since it is smaller than the sum of its proper divisors (66937880880).

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

21976428240 is a wasteful number, since it uses less digits than its factorization.

21976428240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212 (or 203 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 45.

It can be divided in two parts, 219764 and 28240, that added together give a square (248004 = 498²).

The spelling of 21976428240 in words is "twenty-one billion, nine hundred seventy-six million, four hundred twenty-eight thousand, two hundred forty".