21550232 has 16 divisors (see below), whose sum is σ = 44080200. Its totient is φ = 9795520.

The previous prime is 21550231. The next prime is 21550253. The reversal of 21550232 is 23205512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21550231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 122357 + ... + 122532.

Almost surely, 2^21550232 is an apocalyptic number.

21550232 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21550232 is an abundant number, since it is smaller than the sum of its proper divisors (22529968).

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

21550232 is a wasteful number, since it uses less digits than its factorization.

21550232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 244906 (or 244902 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 20.

The square root of 21550232 is about 4642.2227434711. Note that the first 3 decimals coincide. The cubic root of 21550232 is about 278.2812742425.

Adding to 21550232 its reverse (23205512), we get a palindrome (44755744).

The spelling of 21550232 in words is "twenty-one million, five hundred fifty thousand, two hundred thirty-two".