21211356005280 has 1728 divisors, whose sum is σ = 90374337301248. Its totient is φ = 4434544558080.

The previous prime is 21211356005269. The next prime is 21211356005327. The reversal of 21211356005280 is 8250065311212.

21211356005280 is a `hidden beast` number, since 2 + 1 + 2 + 1 + 13 + 560 + 0 + 5 + 2 + 80 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 39207681810 + ... + 39207682350.

It is an arithmetic number, because the mean of its divisors is an integer number (52299963716).

Almost surely, 2^{21211356005280} is an apocalyptic number.

21211356005280 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 21211356005280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45187168650624).

21211356005280 is an abundant number, since it is smaller than the sum of its proper divisors (69162981295968).

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

21211356005280 is a wasteful number, since it uses less digits than its factorization.

21211356005280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 959 (or 931 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

The spelling of 21211356005280 in words is "twenty-one trillion, two hundred eleven billion, three hundred fifty-six million, five thousand, two hundred eighty".