21123232210 has 8 divisors (see below), whose sum is σ = 38021817996. Its totient is φ = 8449292880.

The previous prime is 21123232181. The next prime is 21123232261. The reversal of 21123232210 is 1223232112.

It can be written as a sum of positive squares in 2 ways, for example, as 21101339169 + 21893041 = 145263^2 + 4679^2 .

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

It is a super-3 number, since 3×21123232210³ (a number of 32 digits) contains 333 as substring.

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, 1056161601 + ... + 1056161620.

Almost surely, 2^21123232210 is an apocalyptic number.

21123232210 is a deficient number, since it is larger than the sum of its proper divisors (16898585786).

21123232210 is a wasteful number, since it uses less digits than its factorization.

21123232210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2112323228.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 21123232210 its reverse (1223232112), we get a palindrome (22346464322).

The spelling of 21123232210 in words is "twenty-one billion, one hundred twenty-three million, two hundred thirty-two thousand, two hundred ten".