21523150 has 24 divisors (see below), whose sum is σ = 43673544. Its totient is φ = 7826400.

The previous prime is 21523093. The next prime is 21523171. The reversal of 21523150 is 5132512.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 19017 + ... + 20116.

It is an arithmetic number, because the mean of its divisors is an integer number (1819731).

Almost surely, 2^21523150 is an apocalyptic number.

21523150 is an abundant number, since it is smaller than the sum of its proper divisors (22150394).

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

21523150 is a wasteful number, since it uses less digits than its factorization.

21523150 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39156 (or 39151 counting only the distinct ones).

The product of its (nonzero) digits is 300, while the sum is 19.

The square root of 21523150 is about 4639.3049048322. The cubic root of 21523150 is about 278.1646541112.

Adding to 21523150 its reverse (5132512), we get a palindrome (26655662).

The spelling of 21523150 in words is "twenty-one million, five hundred twenty-three thousand, one hundred fifty".