1321201002100 has 144 divisors (see below), whose sum is σ = 3355068817408. Its totient is φ = 442146418560.

The previous prime is 1321201002091. The next prime is 1321201002139. The reversal of 1321201002100 is 12001021231.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 46430077 + ... + 46458523.

Almost surely, 2^{1321201002100} is an apocalyptic number.

1321201002100 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 1321201002100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1677534408704).

1321201002100 is an abundant number, since it is smaller than the sum of its proper divisors (2033867815308).

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

1321201002100 is a wasteful number, since it uses less digits than its factorization.

1321201002100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30054 (or 30047 counting only the distinct ones).

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

Adding to 1321201002100 its reverse (12001021231), we get a palindrome (1333202023331).

The spelling of 1321201002100 in words is "one trillion, three hundred twenty-one billion, two hundred one million, two thousand, one hundred".