21327945408 has 840 divisors, whose sum is σ = 85139326800. Its totient is φ = 5202247680.

The previous prime is 21327945383. The next prime is 21327945413. The reversal of 21327945408 is 80454972312.

21327945408 is a `hidden beast` number, since 2 + 1 + 32 + 79 + 4 + 540 + 8 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 47500768 + ... + 47501216.

Almost surely, 2^21327945408 is an apocalyptic number.

21327945408 is a gapful number since it is divisible by the number (28) 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 21327945408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42569663400).

21327945408 is an abundant number, since it is smaller than the sum of its proper divisors (63811381392).

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

21327945408 is a wasteful number, since it uses less digits than its factorization.

21327945408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 515 (or 489 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 45.

The spelling of 21327945408 in words is "twenty-one billion, three hundred twenty-seven million, nine hundred forty-five thousand, four hundred eight".