21150324 has 72 divisors (see below), whose sum is σ = 58970912. Its totient is φ = 6350400.

The previous prime is 21150313. The next prime is 21150331. The reversal of 21150324 is 42305112.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 21150297 and 21150306.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19599 + ... + 20649.

Almost surely, 2^21150324 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21150324, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29485456).

21150324 is an abundant number, since it is smaller than the sum of its proper divisors (37820588).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21150324 is a wasteful number, since it uses less digits than its factorization.

21150324 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1117 (or 1112 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 21150324 is about 4598.9481406078. The cubic root of 21150324 is about 276.5491586593.

Adding to 21150324 its reverse (42305112), we get a palindrome (63455436).

The spelling of 21150324 in words is "twenty-one million, one hundred fifty thousand, three hundred twenty-four".