21355232 has 12 divisors (see below), whose sum is σ = 42043176. Its totient is φ = 10677600.

The previous prime is 21355231. The next prime is 21355241. The reversal of 21355232 is 23255312.

It is a junction number, because it is equal to n+sod(n) for n = 21355198 and 21355207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21355231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333644 + ... + 333707.

It is an arithmetic number, because the mean of its divisors is an integer number (3503598).

Almost surely, 2^21355232 is an apocalyptic number.

It is an amenable number.

21355232 is a deficient number, since it is larger than the sum of its proper divisors (20687944).

21355232 is an equidigital number, since it uses as much as digits as its factorization.

21355232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 667361 (or 667353 counting only the distinct ones).

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

The square root of 21355232 is about 4621.1721456791. The cubic root of 21355232 is about 277.4393753342.

The spelling of 21355232 in words is "twenty-one million, three hundred fifty-five thousand, two hundred thirty-two".