21021220102 has 8 divisors (see below), whose sum is σ = 31533036696. Its totient is φ = 10510207872.

The previous prime is 21021220081. The next prime is 21021220117. The reversal of 21021220102 is 20102212012.

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 polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 130848 + ... + 243235.

It is an arithmetic number, because the mean of its divisors is an integer number (3941629587).

Almost surely, 2^21021220102 is an apocalyptic number.

21021220102 is a deficient number, since it is larger than the sum of its proper divisors (10511816594).

21021220102 is a wasteful number, since it uses less digits than its factorization.

21021220102 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 402182.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21021220102 its reverse (20102212012), we get a palindrome (41123432114).

The spelling of 21021220102 in words is "twenty-one billion, twenty-one million, two hundred twenty thousand, one hundred two".