20421325 has 12 divisors (see below), whose sum is σ = 25467988. Its totient is φ = 16243200.

The previous prime is 20421287. The next prime is 20421329. The reversal of 20421325 is 52312402.

It can be written as a sum of positive squares in 6 ways, for example, as 11812969 + 8608356 = 3437^2 + 2934^2 .

It is not a de Polignac number, because 20421325 - 2¹⁹ = 19897037 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20421329) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2269 + ... + 6781.

Almost surely, 2^20421325 is an apocalyptic number.

20421325 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20421325 is a deficient number, since it is larger than the sum of its proper divisors (5046663).

20421325 is a wasteful number, since it uses less digits than its factorization.

20421325 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4704 (or 4699 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 19.

The square root of 20421325 is about 4518.9960168161. The cubic root of 20421325 is about 273.3346181115.

Adding to 20421325 its reverse (52312402), we get a palindrome (72733727).

The spelling of 20421325 in words is "twenty million, four hundred twenty-one thousand, three hundred twenty-five".