25698139 has 4 divisors (see below), whose sum is σ = 25894440. Its totient is φ = 25501840.

The previous prime is 25698131. The next prime is 25698149. The reversal of 25698139 is 93189652.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 25698139 - 2³ = 25698131 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 25698095 and 25698104.

It is not an unprimeable number, because it can be changed into a prime (25698131) 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 3 ways as a sum of consecutive naturals, for example, 97954 + ... + 98215.

It is an arithmetic number, because the mean of its divisors is an integer number (6473610).

Almost surely, 2^25698139 is an apocalyptic number.

25698139 is a deficient number, since it is larger than the sum of its proper divisors (196301).

25698139 is a wasteful number, since it uses less digits than its factorization.

25698139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196300.

The product of its digits is 116640, while the sum is 43.

The square root of 25698139 is about 5069.3331908645. Note that the first 3 decimals coincide. The cubic root of 25698139 is about 295.0986512924.

The spelling of 25698139 in words is "twenty-five million, six hundred ninety-eight thousand, one hundred thirty-nine".