21111000010002 has 72 divisors (see below), whose sum is σ = 53400425236236. Its totient is φ = 6009939077184.

The previous prime is 21111000009989. The next prime is 21111000010021. The reversal of 21111000010002 is 20001000011112.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 21033331336521 + 77668673481 = 4586211^2 + 278691^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 42960333 + ... + 43448960.

Almost surely, 2^{21111000010002} is an apocalyptic number.

21111000010002 is an abundant number, since it is smaller than the sum of its proper divisors (32289425226234).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21111000010002 is a wasteful number, since it uses less digits than its factorization.

21111000010002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86409592 (or 86409582 counting only the distinct ones).

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

Adding to 21111000010002 its reverse (20001000011112), we get a palindrome (41112000021114).

The spelling of 21111000010002 in words is "twenty-one trillion, one hundred eleven billion, ten thousand, two".