25533421 has 4 divisors (see below), whose sum is σ = 25543744. Its totient is φ = 25523100.

The previous prime is 25533419. The next prime is 25533433. The reversal of 25533421 is 12433552.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 25533421 - 2¹ = 25533419 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25533401) 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, 1006 + ... + 7216.

It is an arithmetic number, because the mean of its divisors is an integer number (6385936).

Almost surely, 2^25533421 is an apocalyptic number.

It is an amenable number.

25533421 is a deficient number, since it is larger than the sum of its proper divisors (10323).

25533421 is an equidigital number, since it uses as much as digits as its factorization.

25533421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10322.

The product of its digits is 3600, while the sum is 25.

The square root of 25533421 is about 5053.0605577214. The cubic root of 25533421 is about 294.4667989779.

Adding to 25533421 its reverse (12433552), we get a palindrome (37966973).

The spelling of 25533421 in words is "twenty-five million, five hundred thirty-three thousand, four hundred twenty-one".