21251832 has 32 divisors (see below), whose sum is σ = 60720000. Its totient is φ = 6071904.

The previous prime is 21251831. The next prime is 21251837. The reversal of 21251832 is 23815212.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21251831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 63082 + ... + 63417.

It is an arithmetic number, because the mean of its divisors is an integer number (1897500).

Almost surely, 2^21251832 is an apocalyptic number.

It is an amenable number.

21251832 is an abundant number, since it is smaller than the sum of its proper divisors (39468168).

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

21251832 is a wasteful number, since it uses less digits than its factorization.

21251832 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126515 (or 126511 counting only the distinct ones).

The product of its digits is 960, while the sum is 24.

The square root of 21251832 is about 4609.9709326632. The cubic root of 21251832 is about 276.9908723376.

The spelling of 21251832 in words is "twenty-one million, two hundred fifty-one thousand, eight hundred thirty-two".