21330770 has 16 divisors (see below), whose sum is σ = 38448000. Its totient is φ = 8520624.

The previous prime is 21330761. The next prime is 21330781. The reversal of 21330770 is 7703312.

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 7 ways as a sum of consecutive naturals, for example, 13481 + ... + 14979.

It is an arithmetic number, because the mean of its divisors is an integer number (2403000).

Almost surely, 2^21330770 is an apocalyptic number.

21330770 is a deficient number, since it is larger than the sum of its proper divisors (17117230).

21330770 is a wasteful number, since it uses less digits than its factorization.

21330770 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2929.

The product of its (nonzero) digits is 882, while the sum is 23.

The square root of 21330770 is about 4618.5246562079. The cubic root of 21330770 is about 277.3334010699. Note that the first 3 decimals are identical.

It can be divided in two parts, 213 and 30770, that multiplied together give a triangular number (6554010 = T₃₆₂₀).

The spelling of 21330770 in words is "twenty-one million, three hundred thirty thousand, seven hundred seventy".