1001221200 has 360 divisors, whose sum is σ = 4036938048. Its totient is φ = 225054720.

The previous prime is 1001221187. The next prime is 1001221223. The reversal of 1001221200 is 21221001.

It is a tau number, because it is divible by the number of its divisors (360).

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

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1688104 + ... + 1688696.

Almost surely, 2^1001221200 is an apocalyptic number.

1001221200 is a gapful number since it is divisible by the number (10) 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 1001221200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2018469024).

1001221200 is an abundant number, since it is smaller than the sum of its proper divisors (3035716848).

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

1001221200 is a wasteful number, since it uses less digits than its factorization.

1001221200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 691 (or 677 counting only the distinct ones).

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

The square root of 1001221200 is about 31642.0795776763. The cubic root of 1001221200 is about 1000.4069010757.

Adding to 1001221200 its reverse (21221001), we get a palindrome (1022442201).

The spelling of 1001221200 in words is "one billion, one million, two hundred twenty-one thousand, two hundred".