221211011000 has 128 divisors (see below), whose sum is σ = 592066575360. Its totient is φ = 75781584000.

The previous prime is 221211010981. The next prime is 221211011003. The reversal of 221211011000 is 110112122.

It is a super-2 number, since 2×221211011000² (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 (221211011003) 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 31 ways as a sum of consecutive naturals, for example, 8968685 + ... + 8993315.

It is an arithmetic number, because the mean of its divisors is an integer number (4625520120).

Almost surely, 2^221211011000 is an apocalyptic number.

221211011000 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 221211011000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (296033287680).

221211011000 is an abundant number, since it is smaller than the sum of its proper divisors (370855564360).

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

221211011000 is a wasteful number, since it uses less digits than its factorization.

221211011000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25942 (or 25928 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 221211011000 its reverse (110112122), we get a palindrome (221321123122).

The spelling of 221211011000 in words is "two hundred twenty-one billion, two hundred eleven million, eleven thousand".