21065430 has 32 divisors (see below), whose sum is σ = 52190208. Its totient is φ = 5436000.

The previous prime is 21065423. The next prime is 21065437. The reversal of 21065430 is 3456012.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21065423) and next prime (21065437).

It is a junction number, because it is equal to n+sod(n) for n = 21065397 and 21065406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21065437) 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, 10396 + ... + 12255.

It is an arithmetic number, because the mean of its divisors is an integer number (1630944).

Almost surely, 2^21065430 is an apocalyptic number.

21065430 is an abundant number, since it is smaller than the sum of its proper divisors (31124778).

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

21065430 is a wasteful number, since it uses less digits than its factorization.

21065430 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22692.

The product of its (nonzero) digits is 720, while the sum is 21.

The square root of 21065430 is about 4589.7091411112. The cubic root of 21065430 is about 276.1786545485.

The spelling of 21065430 in words is "twenty-one million, sixty-five thousand, four hundred thirty".