21015112210 has 8 divisors (see below), whose sum is σ = 37827201996. Its totient is φ = 8406044880.

The previous prime is 21015112163. The next prime is 21015112219. The reversal of 21015112210 is 1221151012.

It can be written as a sum of positive squares in 2 ways, for example, as 20747233521 + 267878689 = 144039^2 + 16367^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21015112219) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1050755601 + ... + 1050755620.

Almost surely, 2^21015112210 is an apocalyptic number.

21015112210 is a deficient number, since it is larger than the sum of its proper divisors (16812089786).

21015112210 is a wasteful number, since it uses less digits than its factorization.

21015112210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2101511228.

The product of its (nonzero) digits is 40, while the sum is 16.

Adding to 21015112210 its reverse (1221151012), we get a palindrome (22236263222).

It can be divided in two parts, 21015 and 112210, that added together give a square (133225 = 365²).

The spelling of 21015112210 in words is "twenty-one billion, fifteen million, one hundred twelve thousand, two hundred ten".