1202100000021 has 20 divisors (see below), whose sum is σ = 1808648564800. Its totient is φ = 795634524936.

The previous prime is 1202099999999. The next prime is 1202100000071. The reversal of 1202100000021 is 1200000012021.

It is not a de Polignac number, because 1202100000021 - 2⁶ = 1202099999957 is a prime.

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

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1202099999949 and 1202100000012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1202100000071) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 53372701 + ... + 53395218.

It is an arithmetic number, because the mean of its divisors is an integer number (90432428240).

Almost surely, 2^{1202100000021} is an apocalyptic number.

It is an amenable number.

1202100000021 is a deficient number, since it is larger than the sum of its proper divisors (606548564779).

1202100000021 is a wasteful number, since it uses less digits than its factorization.

1202100000021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106768070 (or 106768061 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 1202100000021 its reverse (1200000012021), we get a palindrome (2402100012042).

The spelling of 1202100000021 in words is "one trillion, two hundred two billion, one hundred million, twenty-one", and thus it is an aban number.