21354530 has 8 divisors (see below), whose sum is σ = 38438172. Its totient is φ = 8541808.

The previous prime is 21354451. The next prime is 21354551. The reversal of 21354530 is 3545312.

It can be written as a sum of positive squares in 2 ways, for example, as 20151121 + 1203409 = 4489^2 + 1097^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 21354496 and 21354505.

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, 1067717 + ... + 1067736.

Almost surely, 2^21354530 is an apocalyptic number.

21354530 is a deficient number, since it is larger than the sum of its proper divisors (17083642).

21354530 is a wasteful number, since it uses less digits than its factorization.

21354530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2135460.

The product of its (nonzero) digits is 1800, while the sum is 23.

The square root of 21354530 is about 4621.0961902994. The cubic root of 21354530 is about 277.4363352584.

Adding to 21354530 its reverse (3545312), we get a palindrome (24899842).

The spelling of 21354530 in words is "twenty-one million, three hundred fifty-four thousand, five hundred thirty".