21002121012101 has 16 divisors (see below), whose sum is σ = 21461693115264. Its totient is φ = 20547426380544.

The previous prime is 21002121012091. The next prime is 21002121012133. The reversal of 21002121012101 is 10121012120012.

It is a cyclic number.

It is not a de Polignac number, because 21002121012101 - 2¹⁰ = 21002121011077 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002121012701) 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, 12225470 + ... + 13837136.

It is an arithmetic number, because the mean of its divisors is an integer number (1341355819704).

Almost surely, 2^{21002121012101} is an apocalyptic number.

It is an amenable number.

21002121012101 is a deficient number, since it is larger than the sum of its proper divisors (459572103163).

21002121012101 is a wasteful number, since it uses less digits than its factorization.

21002121012101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1613180.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21002121012101 its reverse (10121012120012), we get a palindrome (31123133132113).

The spelling of 21002121012101 in words is "twenty-one trillion, two billion, one hundred twenty-one million, twelve thousand, one hundred one".