221000212121020 has 48 divisors (see below), whose sum is σ = 467497675709568. Its totient is φ = 87753019973120.

The previous prime is 221000212120999. The next prime is 221000212121057. The reversal of 221000212121020 is 20121212000122.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 221000212120985 and 221000212121003.

It is a congruent number.

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, 136251309 + ... + 137863771.

It is an arithmetic number, because the mean of its divisors is an integer number (9739534910616).

Almost surely, 2^{221000212121020} is an apocalyptic number.

221000212121020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221000212121020 is an abundant number, since it is smaller than the sum of its proper divisors (246497463588548).

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

221000212121020 is a wasteful number, since it uses less digits than its factorization.

221000212121020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1662630 (or 1662628 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 221000212121020 its reverse (20121212000122), we get a palindrome (241121424121142).

The spelling of 221000212121020 in words is "two hundred twenty-one trillion, two hundred twelve million, one hundred twenty-one thousand, twenty".