221131221000 has 64 divisors (see below), whose sum is σ = 689929418880. Its totient is φ = 58968324800.

The previous prime is 221131220987. The next prime is 221131221001. The reversal of 221131221000 is 122131122.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is not an unprimeable number, because it can be changed into a prime (221131221001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36852204 + ... + 36858203.

It is an arithmetic number, because the mean of its divisors is an integer number (10780147170).

Almost surely, 2^221131221000 is an apocalyptic number.

221131221000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221131221000 is an abundant number, since it is smaller than the sum of its proper divisors (468798197880).

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

221131221000 is a wasteful number, since it uses less digits than its factorization.

221131221000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73710431 (or 73710417 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 221131221000 its reverse (122131122), we get a palindrome (221253352122).

The spelling of 221131221000 in words is "two hundred twenty-one billion, one hundred thirty-one million, two hundred twenty-one thousand".