21232601 has 4 divisors (see below), whose sum is σ = 22865892. Its totient is φ = 19599312.

The previous prime is 21232571. The next prime is 21232639. The reversal of 21232601 is 10623212.

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

It can be written as a sum of positive squares in 2 ways, for example, as 13104400 + 8128201 = 3620^2 + 2851^2 .

It is a cyclic number.

It is not a de Polignac number, because 21232601 - 2¹⁰ = 21231577 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 21232601.

It is not an unprimeable number, because it can be changed into a prime (21232681) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 816626 + ... + 816651.

It is an arithmetic number, because the mean of its divisors is an integer number (5716473).

Almost surely, 2^21232601 is an apocalyptic number.

It is an amenable number.

21232601 is a deficient number, since it is larger than the sum of its proper divisors (1633291).

21232601 is a wasteful number, since it uses less digits than its factorization.

21232601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1633290.

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 21232601 is about 4607.8846556744. The cubic root of 21232601 is about 276.9072964991.

Adding to 21232601 its reverse (10623212), we get a palindrome (31855813).

The spelling of 21232601 in words is "twenty-one million, two hundred thirty-two thousand, six hundred one".