21100002102 has 12 divisors (see below), whose sum is σ = 45716671260. Its totient is φ = 7033334028.

The previous prime is 21100002083. The next prime is 21100002103. The reversal of 21100002102 is 20120000112.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100002103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 586111152 + ... + 586111187.

It is an arithmetic number, because the mean of its divisors is an integer number (3809722605).

Almost surely, 2^21100002102 is an apocalyptic number.

21100002102 is an abundant number, since it is smaller than the sum of its proper divisors (24616669158).

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

21100002102 is a wasteful number, since it uses less digits than its factorization.

21100002102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1172222347 (or 1172222344 counting only the distinct ones).

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

Adding to 21100002102 its reverse (20120000112), we get a palindrome (41220002214).

The spelling of 21100002102 in words is "twenty-one billion, one hundred million, two thousand, one hundred two".