1321101320 has 128 divisors (see below), whose sum is σ = 3776336640. Its totient is φ = 403952640.

The previous prime is 1321101319. The next prime is 1321101343. The reversal of 1321101320 is 231011231.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a junction number, because it is equal to n+sod(n) for n = 1321101295 and 1321101304.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 159194 + ... + 167286.

It is an arithmetic number, because the mean of its divisors is an integer number (29502630).

Almost surely, 2^1321101320 is an apocalyptic number.

1321101320 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 1321101320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1888168320).

1321101320 is an abundant number, since it is smaller than the sum of its proper divisors (2455235320).

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

1321101320 is a wasteful number, since it uses less digits than its factorization.

1321101320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8175 (or 8171 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 1321101320 is about 36346.9575067845. The cubic root of 1321101320 is about 1097.2663028094.

Adding to 1321101320 its reverse (231011231), we get a palindrome (1552112551).

The spelling of 1321101320 in words is "one billion, three hundred twenty-one million, one hundred one thousand, three hundred twenty".