221221231000 has 384 divisors, whose sum is σ = 659885279040. Its totient is φ = 68640768000.

The previous prime is 221221230949. The next prime is 221221231009. The reversal of 221221231000 is 132122122.

It is a happy number.

It is a super-2 number, since 2×221221231000² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221221231009) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 138522202 + ... + 138523798.

Almost surely, 2^221221231000 is an apocalyptic number.

221221231000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221221231000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (329942639520).

221221231000 is an abundant number, since it is smaller than the sum of its proper divisors (438664048040).

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

221221231000 is a wasteful number, since it uses less digits than its factorization.

221221231000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1900 (or 1879 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 221221231000 its reverse (132122122), we get a palindrome (221353353122).

It can be divided in two parts, 2212 and 21231000, that added together give a palindrome (21233212).

The spelling of 221221231000 in words is "two hundred twenty-one billion, two hundred twenty-one million, two hundred thirty-one thousand".