21530150 has 12 divisors (see below), whose sum is σ = 40046172. Its totient is φ = 8612040.

The previous prime is 21530147. The next prime is 21530153. The reversal of 21530150 is 5103512.

It is an interprime number because it is at equal distance from previous prime (21530147) and next prime (21530153).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21530153) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 215252 + ... + 215351.

It is an arithmetic number, because the mean of its divisors is an integer number (3337181).

Almost surely, 2^21530150 is an apocalyptic number.

21530150 is a deficient number, since it is larger than the sum of its proper divisors (18516022).

21530150 is a wasteful number, since it uses less digits than its factorization.

21530150 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 430615 (or 430610 counting only the distinct ones).

The product of its (nonzero) digits is 150, while the sum is 17.

The square root of 21530150 is about 4640.0592668629. The cubic root of 21530150 is about 278.1948067844.

Adding to 21530150 its reverse (5103512), we get a palindrome (26633662).

The spelling of 21530150 in words is "twenty-one million, five hundred thirty thousand, one hundred fifty".