221000101020 has 72 divisors (see below), whose sum is σ = 671128370640. Its totient is φ = 58866424320.

The previous prime is 221000101001. The next prime is 221000101037. The reversal of 221000101020 is 20101000122.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 221000100993 and 221000101011.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 538230 + ... + 855389.

It is an arithmetic number, because the mean of its divisors is an integer number (9321227370).

Almost surely, 2^221000101020 is an apocalyptic number.

221000101020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221000101020 is an abundant number, since it is smaller than the sum of its proper divisors (450128269620).

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

221000101020 is a wasteful number, since it uses less digits than its factorization.

221000101020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1394515 (or 1394510 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 221000101020 its reverse (20101000122), we get a palindrome (241101101142).

The spelling of 221000101020 in words is "two hundred twenty-one billion, one hundred one thousand, twenty".