21702330 has 112 divisors (see below), whose sum is σ = 63350280. Its totient is φ = 5318784.

The previous prime is 21702323. The next prime is 21702341. The reversal of 21702330 is 3320712.

It can be written as a sum of positive squares in 4 ways, for example, as 18429849 + 3272481 = 4293^2 + 1809^2 .

It is a super-2 number, since 2×21702330² = 941982254857800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a Curzon number.

It is an unprimeable number.

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 55 ways as a sum of consecutive naturals, for example, 94656 + ... + 94884.

Almost surely, 2^21702330 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21702330, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31675140).

21702330 is an abundant number, since it is smaller than the sum of its proper divisors (41647950).

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

21702330 is a wasteful number, since it uses less digits than its factorization.

21702330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 267 (or 252 counting only the distinct ones).

The product of its (nonzero) digits is 252, while the sum is 18.

The square root of 21702330 is about 4658.5759626736. The cubic root of 21702330 is about 278.9344278783.

The spelling of 21702330 in words is "twenty-one million, seven hundred two thousand, three hundred thirty".