1320120100 has 72 divisors (see below), whose sum is σ = 3115286720. Its totient is φ = 482647680.

The previous prime is 1320120073. The next prime is 1320120119. The reversal of 1320120100 is 10210231.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 128971 + ... + 138829.

Almost surely, 2^1320120100 is an apocalyptic number.

1320120100 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 1320120100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1557643360).

1320120100 is an abundant number, since it is smaller than the sum of its proper divisors (1795166620).

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

1320120100 is a wasteful number, since it uses less digits than its factorization.

1320120100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9989 (or 9982 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 10.

The square root of 1320120100 is about 36333.4570334286. The cubic root of 1320120100 is about 1096.9945784305.

Adding to 1320120100 its reverse (10210231), we get a palindrome (1330330331).

The spelling of 1320120100 in words is "one billion, three hundred twenty million, one hundred twenty thousand, one hundred".