21210222001020 has 48 divisors (see below), whose sum is σ = 63956977113120. Its totient is φ = 5220977723136.

The previous prime is 21210222001013. The next prime is 21210222001021. The reversal of 21210222001020 is 2010022201212.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21210222001021) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13596295375 + ... + 13596296934.

It is an arithmetic number, because the mean of its divisors is an integer number (1332437023190).

Almost surely, 2^{21210222001020} is an apocalyptic number.

21210222001020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21210222001020 is an abundant number, since it is smaller than the sum of its proper divisors (42746755112100).

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

21210222001020 is a wasteful number, since it uses less digits than its factorization.

21210222001020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27192592334 (or 27192592332 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21210222001020 its reverse (2010022201212), we get a palindrome (23220244202232).

The spelling of 21210222001020 in words is "twenty-one trillion, two hundred ten billion, two hundred twenty-two million, one thousand, twenty".