25278591 has 16 divisors (see below), whose sum is σ = 37185120. Its totient is φ = 15175680.

The previous prime is 25278577. The next prime is 25278599. The reversal of 25278591 is 19587252.

It is not a de Polignac number, because 25278591 - 2⁹ = 25278079 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25278599) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6306 + ... + 9503.

It is an arithmetic number, because the mean of its divisors is an integer number (2324070).

Almost surely, 2^25278591 is an apocalyptic number.

25278591 is a deficient number, since it is larger than the sum of its proper divisors (11906529).

25278591 is a wasteful number, since it uses less digits than its factorization.

25278591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15866.

The product of its digits is 50400, while the sum is 39.

The square root of 25278591 is about 5027.7819165115. The cubic root of 25278591 is about 293.4839041310.

The spelling of 25278591 in words is "twenty-five million, two hundred seventy-eight thousand, five hundred ninety-one".