21845430 has 32 divisors (see below), whose sum is σ = 58255200. Its totient is φ = 5825376.

The previous prime is 21845401. The next prime is 21845431. The reversal of 21845430 is 3454812.

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 = 21845394 and 21845403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21845431) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 40185 + ... + 40724.

It is an arithmetic number, because the mean of its divisors is an integer number (1820475).

Almost surely, 2^21845430 is an apocalyptic number.

21845430 is an abundant number, since it is smaller than the sum of its proper divisors (36409770).

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

21845430 is a wasteful number, since it uses less digits than its factorization.

21845430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80925 (or 80919 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 21845430 is about 4673.9094984820. The cubic root of 21845430 is about 279.5461610495.

The spelling of 21845430 in words is "twenty-one million, eight hundred forty-five thousand, four hundred thirty".