21010002111 has 12 divisors (see below), whose sum is σ = 34683178192. Its totient is φ = 12005715456.

The previous prime is 21010002061. The next prime is 21010002113. The reversal of 21010002111 is 11120001012.

It is a happy number.

It is not a de Polignac number, because 21010002111 - 2¹⁰ = 21010001087 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 = 21010002093 and 21010002102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21010002113) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 166745986 + ... + 166746111.

Almost surely, 2^21010002111 is an apocalyptic number.

21010002111 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21010002111 is a deficient number, since it is larger than the sum of its proper divisors (13673176081).

21010002111 is a wasteful number, since it uses less digits than its factorization.

21010002111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333492110 (or 333492107 counting only the distinct ones).

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

Adding to 21010002111 its reverse (11120001012), we get a palindrome (32130003123).

The spelling of 21010002111 in words is "twenty-one billion, ten million, two thousand, one hundred eleven".