25537421 has 12 divisors (see below), whose sum is σ = 31604832. Its totient is φ = 20204496.

The previous prime is 25537409. The next prime is 25537423. The reversal of 25537421 is 12473552.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-25537421 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25537423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9611 + ... + 11976.

It is an arithmetic number, because the mean of its divisors is an integer number (2633736).

Almost surely, 2^25537421 is an apocalyptic number.

It is an amenable number.

25537421 is a deficient number, since it is larger than the sum of its proper divisors (6067411).

25537421 is a wasteful number, since it uses less digits than its factorization.

25537421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21620 (or 21607 counting only the distinct ones).

The product of its digits is 8400, while the sum is 29.

The square root of 25537421 is about 5053.4563419505. The cubic root of 25537421 is about 294.4821749785.

The spelling of 25537421 in words is "twenty-five million, five hundred thirty-seven thousand, four hundred twenty-one".