21432735 has 16 divisors (see below), whose sum is σ = 38102880. Its totient is φ = 11430720.

The previous prime is 21432701. The next prime is 21432737. The reversal of 21432735 is 53723412.

It is not a de Polignac number, because 21432735 - 2¹⁵ = 21399967 is a prime.

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

It is a junction number, because it is equal to n+sod(n) for n = 21432699 and 21432708.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21432737) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 79246 + ... + 79515.

It is an arithmetic number, because the mean of its divisors is an integer number (2381430).

Almost surely, 2^21432735 is an apocalyptic number.

21432735 is a deficient number, since it is larger than the sum of its proper divisors (16670145).

21432735 is a wasteful number, since it uses less digits than its factorization.

21432735 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 158775 (or 158769 counting only the distinct ones).

The product of its digits is 5040, while the sum is 27.

The square root of 21432735 is about 4629.5501941333. The cubic root of 21432735 is about 277.7746003488.

The spelling of 21432735 in words is "twenty-one million, four hundred thirty-two thousand, seven hundred thirty-five".