21249432 has 32 divisors (see below), whose sum is σ = 59026800. Its totient is φ = 7083072.

The previous prime is 21249331. The next prime is 21249443. The reversal of 21249432 is 23494212.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 21249396 and 21249405.

It is a congruent number.

It is an unprimeable number.

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, 48973 + ... + 49404.

Almost surely, 2^21249432 is an apocalyptic number.

It is an amenable number.

21249432 is an abundant number, since it is smaller than the sum of its proper divisors (37777368).

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

21249432 is a wasteful number, since it uses less digits than its factorization.

21249432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98392 (or 98382 counting only the distinct ones).

The product of its digits is 3456, while the sum is 27.

The square root of 21249432 is about 4609.7106199847. The cubic root of 21249432 is about 276.9804449523.

The spelling of 21249432 in words is "twenty-one million, two hundred forty-nine thousand, four hundred thirty-two".