1011321220 has 48 divisors (see below), whose sum is σ = 2613881088. Its totient is φ = 320065920.

The previous prime is 1011321217. The next prime is 1011321229. The reversal of 1011321220 is 221231101.

It is a super-2 number, since 2×1011321220² = 2045541220044576800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a self number, because there is not a number n which added to its sum of digits gives 1011321220.

It is not an unprimeable number, because it can be changed into a prime (1011321229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 276016 + ... + 279655.

It is an arithmetic number, because the mean of its divisors is an integer number (54455856).

Almost surely, 2^1011321220 is an apocalyptic number.

1011321220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1011321220 is an abundant number, since it is smaller than the sum of its proper divisors (1602559868).

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

1011321220 is a wasteful number, since it uses less digits than its factorization.

1011321220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 555700 (or 555698 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 13.

The square root of 1011321220 is about 31801.2770183840. The cubic root of 1011321220 is about 1003.7595877864.

Adding to 1011321220 its reverse (221231101), we get a palindrome (1232552321).

The spelling of 1011321220 in words is "one billion, eleven million, three hundred twenty-one thousand, two hundred twenty".