21630011 has 8 divisors (see below), whose sum is σ = 23790144. Its totient is φ = 19540800.

The previous prime is 21629977. The next prime is 21630013. The reversal of 21630011 is 11003612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21630011 - 2⁶ = 21629947 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21630013) 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 7 ways as a sum of consecutive naturals, for example, 17090 + ... + 18311.

It is an arithmetic number, because the mean of its divisors is an integer number (2973768).

Almost surely, 2^21630011 is an apocalyptic number.

21630011 is a deficient number, since it is larger than the sum of its proper divisors (2160133).

21630011 is a wasteful number, since it uses less digits than its factorization.

21630011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35461.

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 21630011 is about 4650.8075642839. The cubic root of 21630011 is about 278.6242506264.

Adding to 21630011 its reverse (11003612), we get a palindrome (32633623).

The spelling of 21630011 in words is "twenty-one million, six hundred thirty thousand, eleven".