21135250080 has 384 divisors, whose sum is σ = 85501785600. Its totient is φ = 4776026112.

The previous prime is 21135250063. The next prime is 21135250127. The reversal of 21135250080 is 8005253112.

It is a happy number.

21135250080 is a `hidden beast` number, since 21 + 13 + 52 + 500 + 80 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2687434 + ... + 2695286.

It is an arithmetic number, because the mean of its divisors is an integer number (222660900).

Almost surely, 2^21135250080 is an apocalyptic number.

21135250080 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 21135250080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42750892800).

21135250080 is an abundant number, since it is smaller than the sum of its proper divisors (64366535520).

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

21135250080 is a wasteful number, since it uses less digits than its factorization.

21135250080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7973 (or 7959 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 27.

The spelling of 21135250080 in words is "twenty-one billion, one hundred thirty-five million, two hundred fifty thousand, eighty".