21268440000 has 560 divisors, whose sum is σ = 79984396800. Its totient is φ = 5537664000.

The previous prime is 21268439993. The next prime is 21268440029. The reversal of 21268440000 is 4486212.

21268440000 is a `hidden beast` number, since 212 + 6 + 8 + 440 + 0 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 50759791 + ... + 50760209.

It is an arithmetic number, because the mean of its divisors is an integer number (142829280).

Almost surely, 2^21268440000 is an apocalyptic number.

21268440000 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 21268440000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39992198400).

21268440000 is an abundant number, since it is smaller than the sum of its proper divisors (58715956800).

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

21268440000 is an equidigital number, since it uses as much as digits as its factorization.

21268440000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 507 (or 476 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The spelling of 21268440000 in words is "twenty-one billion, two hundred sixty-eight million, four hundred forty thousand".