221012221021220 has 48 divisors (see below), whose sum is σ = 467214047612928. Its totient is φ = 87817512854400.

The previous prime is 221012221021219. The next prime is 221012221021243. The reversal of 221012221021220 is 22120122210122.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 221012221021192 and 221012221021201.

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, 23765744 + ... + 31730663.

It is an arithmetic number, because the mean of its divisors is an integer number (9733625991936).

Almost surely, 2^{221012221021220} is an apocalyptic number.

221012221021220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221012221021220 is an abundant number, since it is smaller than the sum of its proper divisors (246201826591708).

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

221012221021220 is a wasteful number, since it uses less digits than its factorization.

221012221021220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55497740 (or 55497738 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 221012221021220 its reverse (22120122210122), we get a palindrome (243132343231342).

The spelling of 221012221021220 in words is "two hundred twenty-one trillion, twelve billion, two hundred twenty-one million, twenty-one thousand, two hundred twenty".