21125234 has 24 divisors (see below), whose sum is σ = 34833708. Its totient is φ = 9551520.

The previous prime is 21125233. The next prime is 21125239. The reversal of 21125234 is 43252112.

It can be written as a sum of positive squares in 2 ways, for example, as 15626209 + 5499025 = 3953^2 + 2345^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21125233) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 116624 + ... + 116804.

Almost surely, 2^21125234 is an apocalyptic number.

21125234 is a deficient number, since it is larger than the sum of its proper divisors (13708474).

21125234 is a wasteful number, since it uses less digits than its factorization.

21125234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 330 (or 263 counting only the distinct ones).

The product of its digits is 480, while the sum is 20.

The square root of 21125234 is about 4596.2195334862. The cubic root of 21125234 is about 276.4397613771.

Adding to 21125234 its reverse (43252112), we get a palindrome (64377346).

The spelling of 21125234 in words is "twenty-one million, one hundred twenty-five thousand, two hundred thirty-four".