21423120102 has 96 divisors (see below), whose sum is σ = 48827750400. Its totient is φ = 6780366144.

The previous prime is 21423120097. The next prime is 21423120107. The reversal of 21423120102 is 20102132412.

It is a happy number.

21423120102 is a `hidden beast` number, since 21 + 423 + 120 + 102 = 666.

It is an interprime number because it is at equal distance from previous prime (21423120097) and next prime (21423120107).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21423120107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 13740799 + ... + 13742357.

It is an arithmetic number, because the mean of its divisors is an integer number (508622400).

Almost surely, 2^21423120102 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21423120102, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24413875200).

21423120102 is an abundant number, since it is smaller than the sum of its proper divisors (27404630298).

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

21423120102 is a wasteful number, since it uses less digits than its factorization.

21423120102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2090 (or 2087 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 21423120102 its reverse (20102132412), we get a palindrome (41525252514).

The spelling of 21423120102 in words is "twenty-one billion, four hundred twenty-three million, one hundred twenty thousand, one hundred two".