1321100001 has 24 divisors (see below), whose sum is σ = 2163208320. Its totient is φ = 770194656.

The previous prime is 1321099993. The next prime is 1321100009. The reversal of 1321100001 is 1000011231.

It is an interprime number because it is at equal distance from previous prime (1321099993) and next prime (1321100009).

It is not a de Polignac number, because 1321100001 - 2³ = 1321099993 is a prime.

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 (1321100009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 294921 + ... + 299366.

It is an arithmetic number, because the mean of its divisors is an integer number (90133680).

Almost surely, 2^1321100001 is an apocalyptic number.

It is an amenable number.

1321100001 is a deficient number, since it is larger than the sum of its proper divisors (842108319).

1321100001 is a wasteful number, since it uses less digits than its factorization.

1321100001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 594325 (or 594322 counting only the distinct ones).

The product of its (nonzero) digits is 6, while the sum is 9.

The square root of 1321100001 is about 36346.9393622077. The cubic root of 1321100001 is about 1097.2659376356.

Adding to 1321100001 its reverse (1000011231), we get a palindrome (2321111232).

The spelling of 1321100001 in words is "one billion, three hundred twenty-one million, one hundred thousand, one".