1001221100 has 36 divisors (see below), whose sum is σ = 2370166008. Its totient is φ = 364080000.

The previous prime is 1001221097. The next prime is 1001221127. The reversal of 1001221100 is 11221001.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 454001 + ... + 456200.

Almost surely, 2^1001221100 is an apocalyptic number.

1001221100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1001221100 is an abundant number, since it is smaller than the sum of its proper divisors (1368944908).

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

1001221100 is a wasteful number, since it uses less digits than its factorization.

1001221100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 910226 (or 910219 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 8.

The square root of 1001221100 is about 31642.0779975020. The cubic root of 1001221100 is about 1000.4068677695.

Adding to 1001221100 its reverse (11221001), we get a palindrome (1012442101).

Subtracting from 1001221100 its reverse (11221001), we obtain a palindrome (990000099).

The spelling of 1001221100 in words is "one billion, one million, two hundred twenty-one thousand, one hundred".