21235007 has 4 divisors (see below), whose sum is σ = 21752976. Its totient is φ = 20717040.

The previous prime is 21235001. The next prime is 21235009. The reversal of 21235007 is 70053212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21235007 - 2¹⁰ = 21233983 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21235007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21235001) 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 3 ways as a sum of consecutive naturals, for example, 258923 + ... + 259004.

It is an arithmetic number, because the mean of its divisors is an integer number (5438244).

Almost surely, 2^21235007 is an apocalyptic number.

21235007 is a deficient number, since it is larger than the sum of its proper divisors (517969).

21235007 is an equidigital number, since it uses as much as digits as its factorization.

21235007 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 517968.

The product of its (nonzero) digits is 420, while the sum is 20.

The square root of 21235007 is about 4608.1457225222. The cubic root of 21235007 is about 276.9177554751.

Adding to 21235007 its reverse (70053212), we get a palindrome (91288219).

The spelling of 21235007 in words is "twenty-one million, two hundred thirty-five thousand, seven".