21030667 has 16 divisors (see below), whose sum is σ = 24837120. Its totient is φ = 17434368.

The previous prime is 21030637. The next prime is 21030677. The reversal of 21030667 is 76603012.

It is not a de Polignac number, because 21030667 - 2¹¹ = 21028619 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21030637) 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 15 ways as a sum of consecutive naturals, for example, 31584 + ... + 32242.

It is an arithmetic number, because the mean of its divisors is an integer number (1552320).

Almost surely, 2^21030667 is an apocalyptic number.

21030667 is a deficient number, since it is larger than the sum of its proper divisors (3806453).

21030667 is an equidigital number, since it uses as much as digits as its factorization.

21030667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 810.

The product of its (nonzero) digits is 1512, while the sum is 25.

The square root of 21030667 is about 4585.9205182820. The cubic root of 21030667 is about 276.0266506156.

Adding to 21030667 its reverse (76603012), we get a palindrome (97633679).

The spelling of 21030667 in words is "twenty-one million, thirty thousand, six hundred sixty-seven".