21121110210 has 32 divisors (see below), whose sum is σ = 50695103232. Its totient is φ = 5631802880.

The previous prime is 21121110209. The next prime is 21121110211. The reversal of 21121110210 is 1201112112.

It is an interprime number because it is at equal distance from previous prime (21121110209) and next prime (21121110211).

It is a super-2 number, since 2×21121110210² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21121110211) 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, 430855 + ... + 477365.

It is an arithmetic number, because the mean of its divisors is an integer number (1584221976).

Almost surely, 2^21121110210 is an apocalyptic number.

21121110210 is an abundant number, since it is smaller than the sum of its proper divisors (29573993022).

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

21121110210 is a wasteful number, since it uses less digits than its factorization.

21121110210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61658.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21121110210 its reverse (1201112112), we get a palindrome (22322222322).

The spelling of 21121110210 in words is "twenty-one billion, one hundred twenty-one million, one hundred ten thousand, two hundred ten".