1011101220 has 72 divisors (see below), whose sum is σ = 3149919864. Its totient is φ = 262338048.

The previous prime is 1011101219. The next prime is 1011101227. The reversal of 1011101220 is 221011101.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 301091904 + 710009316 = 17352^2 + 26646^2 .

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

It is not an unprimeable number, because it can be changed into a prime (1011101227) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 69249 + ... + 82568.

It is an arithmetic number, because the mean of its divisors is an integer number (43748887).

Almost surely, 2^1011101220 is an apocalyptic number.

1011101220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1011101220 is an abundant number, since it is smaller than the sum of its proper divisors (2138818644).

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

1011101220 is a wasteful number, since it uses less digits than its factorization.

1011101220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151869 (or 151864 counting only the distinct ones).

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

The square root of 1011101220 is about 31797.8178496575. The cubic root of 1011101220 is about 1003.6867974867.

Adding to 1011101220 its reverse (221011101), we get a palindrome (1232112321).

The spelling of 1011101220 in words is "one billion, eleven million, one hundred one thousand, two hundred twenty".