2121101001 has 24 divisors (see below), whose sum is σ = 3088987200. Its totient is φ = 1402495776.

The previous prime is 2121100997. The next prime is 2121101029. The reversal of 2121101001 is 1001011212.

It is a happy number.

It is not a de Polignac number, because 2121101001 - 2² = 2121100997 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 (2121101071) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 619771 + ... + 623183.

It is an arithmetic number, because the mean of its divisors is an integer number (128707800).

Almost surely, 2^2121101001 is an apocalyptic number.

It is an amenable number.

2121101001 is a deficient number, since it is larger than the sum of its proper divisors (967886199).

2121101001 is a wasteful number, since it uses less digits than its factorization.

2121101001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3965 (or 3962 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

The square root of 2121101001 is about 46055.4122878083. The cubic root of 2121101001 is about 1284.8540061342.

Adding to 2121101001 its reverse (1001011212), we get a palindrome (3122112213).

The spelling of 2121101001 in words is "two billion, one hundred twenty-one million, one hundred one thousand, one".