21560234 has 4 divisors (see below), whose sum is σ = 32340354. Its totient is φ = 10780116.

The previous prime is 21560213. The next prime is 21560237. The reversal of 21560234 is 43206512.

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., 20566225 + 994009 = 4535^2 + 997^2 .

It is not an unprimeable number, because it can be changed into a prime (21560237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5390057 + ... + 5390060.

Almost surely, 2^21560234 is an apocalyptic number.

21560234 is a deficient number, since it is larger than the sum of its proper divisors (10780120).

21560234 is a wasteful number, since it uses less digits than its factorization.

21560234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10780119.

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 21560234 is about 4643.2999041630. The cubic root of 21560234 is about 278.3243200096.

Adding to 21560234 its reverse (43206512), we get a palindrome (64766746).

The spelling of 21560234 in words is "twenty-one million, five hundred sixty thousand, two hundred thirty-four".