25778542 has 4 divisors (see below), whose sum is σ = 38667816. Its totient is φ = 12889270.

The previous prime is 25778527. The next prime is 25778549. The reversal of 25778542 is 24587752.

It is a happy number.

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

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 25778495 and 25778504.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25778549) 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 as a sum of consecutive naturals, namely, 6444634 + ... + 6444637.

It is an arithmetic number, because the mean of its divisors is an integer number (9666954).

Almost surely, 2^25778542 is an apocalyptic number.

25778542 is a deficient number, since it is larger than the sum of its proper divisors (12889274).

25778542 is a wasteful number, since it uses less digits than its factorization.

25778542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12889273.

The product of its digits is 156800, while the sum is 40.

The square root of 25778542 is about 5077.2573304886. The cubic root of 25778542 is about 295.4060939792.

The spelling of 25778542 in words is "twenty-five million, seven hundred seventy-eight thousand, five hundred forty-two".