21002111021101 has 16 divisors (see below), whose sum is σ = 25046602272000. Its totient is φ = 17218705097088.

The previous prime is 21002111021011. The next prime is 21002111021123. The reversal of 21002111021101 is 10112011120012.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21002111021101 - 2⁷ = 21002111020973 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002111021161) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5179135 + ... + 8296243.

It is an arithmetic number, because the mean of its divisors is an integer number (1565412642000).

Almost surely, 2^{21002111021101} is an apocalyptic number.

It is an amenable number.

21002111021101 is a deficient number, since it is larger than the sum of its proper divisors (4044491250899).

21002111021101 is a wasteful number, since it uses less digits than its factorization.

21002111021101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3158988.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 21002111021101 its reverse (10112011120012), we get a palindrome (31114122141113).

The spelling of 21002111021101 in words is "twenty-one trillion, two billion, one hundred eleven million, twenty-one thousand, one hundred one".