25781478 has 8 divisors (see below), whose sum is σ = 51562968. Its totient is φ = 8593824.

The previous prime is 25781473. The next prime is 25781513. The reversal of 25781478 is 87418752.

It is a sphenic number, since it is the product of 3 distinct primes.

25781478 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25781471) 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, 2148451 + ... + 2148462.

It is an arithmetic number, because the mean of its divisors is an integer number (6445371).

Almost surely, 2^25781478 is an apocalyptic number.

25781478 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

25781478 is a wasteful number, since it uses less digits than its factorization.

25781478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4296918.

The product of its digits is 125440, while the sum is 42.

The square root of 25781478 is about 5077.5464547358. The cubic root of 25781478 is about 295.4173084662.

The spelling of 25781478 in words is "twenty-five million, seven hundred eighty-one thousand, four hundred seventy-eight".