21547234 has 4 divisors (see below), whose sum is σ = 32320854. Its totient is φ = 10773616.

The previous prime is 21547231. The next prime is 21547237. The reversal of 21547234 is 43274512.

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

It is an interprime number because it is at equal distance from previous prime (21547231) and next prime (21547237).

It can be written as a sum of positive squares in only one way, i.e., 21483225 + 64009 = 4635^2 + 253^2 .

It is not an unprimeable number, because it can be changed into a prime (21547231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5386807 + ... + 5386810.

Almost surely, 2^21547234 is an apocalyptic number.

21547234 is a deficient number, since it is larger than the sum of its proper divisors (10773620).

21547234 is a wasteful number, since it uses less digits than its factorization.

21547234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10773619.

The product of its digits is 6720, while the sum is 28.

The square root of 21547234 is about 4641.8998265796. The cubic root of 21547234 is about 278.2683691076.

The spelling of 21547234 in words is "twenty-one million, five hundred forty-seven thousand, two hundred thirty-four".