1011100221 has 48 divisors (see below), whose sum is σ = 1553610240. Its totient is φ = 632759040.

The previous prime is 1011100199. The next prime is 1011100229. The reversal of 1011100221 is 1220011101.

It is a happy number.

It is not a de Polignac number, because 1011100221 - 2¹⁸ = 1010838077 is a prime.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1011100229) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1405900 + ... + 1406618.

It is an arithmetic number, because the mean of its divisors is an integer number (32366880).

Almost surely, 2^1011100221 is an apocalyptic number.

It is an amenable number.

1011100221 is a deficient number, since it is larger than the sum of its proper divisors (542510019).

1011100221 is a wasteful number, since it uses less digits than its factorization.

1011100221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 906 (or 903 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

The square root of 1011100221 is about 31797.8021410286. The cubic root of 1011100221 is about 1003.6864669285.

Adding to 1011100221 its reverse (1220011101), we get a palindrome (2231111322).

The spelling of 1011100221 in words is "one billion, eleven million, one hundred thousand, two hundred twenty-one".