21012020102 has 8 divisors (see below), whose sum is σ = 31916992800. Its totient is φ = 10373022504.

The previous prime is 21012020059. The next prime is 21012020119. The reversal of 21012020102 is 20102021012.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 66493577 + ... + 66493892.

It is an arithmetic number, because the mean of its divisors is an integer number (3989624100).

Almost surely, 2^21012020102 is an apocalyptic number.

21012020102 is a deficient number, since it is larger than the sum of its proper divisors (10904972698).

21012020102 is a wasteful number, since it uses less digits than its factorization.

21012020102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132987550.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21012020102 its reverse (20102021012), we get a palindrome (41114041114).

The spelling of 21012020102 in words is "twenty-one billion, twelve million, twenty thousand, one hundred two".