21278532350220 has 48 divisors (see below), whose sum is σ = 60965469438720. Its totient is φ = 5542315402176.

The previous prime is 21278532350209. The next prime is 21278532350249. The reversal of 21278532350220 is 2205323587212.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4123744000 + ... + 4123749159.

It is an arithmetic number, because the mean of its divisors is an integer number (1270113946640).

Almost surely, 2^{21278532350220} is an apocalyptic number.

21278532350220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21278532350220 is an abundant number, since it is smaller than the sum of its proper divisors (39686937088500).

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

21278532350220 is a wasteful number, since it uses less digits than its factorization.

21278532350220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8247493214 (or 8247493212 counting only the distinct ones).

The product of its (nonzero) digits is 403200, while the sum is 42.

The spelling of 21278532350220 in words is "twenty-one trillion, two hundred seventy-eight billion, five hundred thirty-two million, three hundred fifty thousand, two hundred twenty".