21002120262 has 16 divisors (see below), whose sum is σ = 46671378480. Its totient is φ = 7000706736.

The previous prime is 21002120261. The next prime is 21002120273. The reversal of 21002120262 is 26202120012.

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 (21002120261) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 194464023 + ... + 194464130.

It is an arithmetic number, because the mean of its divisors is an integer number (2916961155).

Almost surely, 2^21002120262 is an apocalyptic number.

21002120262 is an abundant number, since it is smaller than the sum of its proper divisors (25669258218).

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

21002120262 is a wasteful number, since it uses less digits than its factorization.

21002120262 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 388928164 (or 388928158 counting only the distinct ones).

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

Adding to 21002120262 its reverse (26202120012), we get a palindrome (47204240274).

The spelling of 21002120262 in words is "twenty-one billion, two million, one hundred twenty thousand, two hundred sixty-two".