25491839 has 4 divisors (see below), whose sum is σ = 25909800. Its totient is φ = 25073880.

The previous prime is 25491793. The next prime is 25491871. The reversal of 25491839 is 93819452.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25491839 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 25491796 and 25491805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25491139) 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, 208889 + ... + 209010.

It is an arithmetic number, because the mean of its divisors is an integer number (6477450).

Almost surely, 2^25491839 is an apocalyptic number.

25491839 is a deficient number, since it is larger than the sum of its proper divisors (417961).

25491839 is an equidigital number, since it uses as much as digits as its factorization.

25491839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 417960.

The product of its digits is 77760, while the sum is 41.

The square root of 25491839 is about 5048.9443451082. The cubic root of 25491839 is about 294.3068625646.

The spelling of 25491839 in words is "twenty-five million, four hundred ninety-one thousand, eight hundred thirty-nine".