25436421 has 18 divisors (see below), whose sum is σ = 38781990. Its totient is φ = 16063056.

The previous prime is 25436419. The next prime is 25436479. The reversal of 25436421 is 12463452.

It can be written as a sum of positive squares in only one way, i.e., 17313921 + 8122500 = 4161^2 + 2850^2 .

It is not a de Polignac number, because 25436421 - 2¹ = 25436419 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25436491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 666 + ... + 7163.

It is an arithmetic number, because the mean of its divisors is an integer number (2154555).

Almost surely, 2^25436421 is an apocalyptic number.

It is an amenable number.

25436421 is a deficient number, since it is larger than the sum of its proper divisors (13345569).

25436421 is a wasteful number, since it uses less digits than its factorization.

25436421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7873 (or 7851 counting only the distinct ones).

The product of its digits is 5760, while the sum is 27.

The square root of 25436421 is about 5043.4532812350. The cubic root of 25436421 is about 294.0934383000.

Adding to 25436421 its reverse (12463452), we get a palindrome (37899873).

The spelling of 25436421 in words is "twenty-five million, four hundred thirty-six thousand, four hundred twenty-one".