21211946280 has 224 divisors, whose sum is σ = 81780883200. Its totient is φ = 4848398208.

The previous prime is 21211946257. The next prime is 21211946293. The reversal of 21211946280 is 8264911212.

21211946280 is a `hidden beast` number, since 2 + 1 + 2 + 119 + 462 + 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 55 ways as a sum of consecutive naturals, for example, 152161 + ... + 256079.

Almost surely, 2^21211946280 is an apocalyptic number.

21211946280 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 21211946280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40890441600).

21211946280 is an abundant number, since it is smaller than the sum of its proper divisors (60568936920).

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

21211946280 is a wasteful number, since it uses less digits than its factorization.

21211946280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103955 (or 103936 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The spelling of 21211946280 in words is "twenty-one billion, two hundred eleven million, nine hundred forty-six thousand, two hundred eighty".