2100101001021 has 24 divisors (see below), whose sum is σ = 3068948712960. Its totient is φ = 1383750218016.

The previous prime is 2100101001007. The next prime is 2100101001077. The reversal of 2100101001021 is 1201001010012.

It is a happy number.

It is not a de Polignac number, because 2100101001021 - 2¹⁷ = 2100100869949 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 2100101000994 and 2100101001012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2100101001121) 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, 1753581 + ... + 2697266.

It is an arithmetic number, because the mean of its divisors is an integer number (127872863040).

Almost surely, 2^{2100101001021} is an apocalyptic number.

It is an amenable number.

2100101001021 is a deficient number, since it is larger than the sum of its proper divisors (968847711939).

2100101001021 is a wasteful number, since it uses less digits than its factorization.

2100101001021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4451465 (or 4451462 counting only the distinct ones).

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

Adding to 2100101001021 its reverse (1201001010012), we get a palindrome (3301102011033).

The spelling of 2100101001021 in words is "two trillion, one hundred billion, one hundred one million, one thousand, twenty-one".