21197234 has 4 divisors (see below), whose sum is σ = 31795854. Its totient is φ = 10598616.

The previous prime is 21197221. The next prime is 21197251. The reversal of 21197234 is 43279112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 15976009 + 5221225 = 3997^2 + 2285^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21197197 and 21197206.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5299307 + ... + 5299310.

Almost surely, 2^21197234 is an apocalyptic number.

21197234 is a deficient number, since it is larger than the sum of its proper divisors (10598620).

21197234 is a wasteful number, since it uses less digits than its factorization.

21197234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10598619.

The product of its digits is 3024, while the sum is 29.

The square root of 21197234 is about 4604.0453950846. The cubic root of 21197234 is about 276.7534635171.

The spelling of 21197234 in words is "twenty-one million, one hundred ninety-seven thousand, two hundred thirty-four".