21715330 has 64 divisors (see below), whose sum is σ = 49190400. Its totient is φ = 6858432.

The previous prime is 21715327. The next prime is 21715333. The reversal of 21715330 is 3351712.

21715330 is nontrivially palindromic in base 9.

It is an interprime number because it is at equal distance from previous prime (21715327) and next prime (21715333).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21715333) 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 31 ways as a sum of consecutive naturals, for example, 44347 + ... + 44833.

It is an arithmetic number, because the mean of its divisors is an integer number (768600).

Almost surely, 2^21715330 is an apocalyptic number.

21715330 is an abundant number, since it is smaller than the sum of its proper divisors (27475070).

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

21715330 is a wasteful number, since it uses less digits than its factorization.

21715330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 528 (or 514 counting only the distinct ones).

The product of its (nonzero) digits is 630, while the sum is 22.

The square root of 21715330 is about 4659.9710299529. The cubic root of 21715330 is about 278.9901119725.

The spelling of 21715330 in words is "twenty-one million, seven hundred fifteen thousand, three hundred thirty".