25478863641 has 81 divisors (see below), whose sum is σ = 47125383669. Its totient is φ = 13216618800.

The previous prime is 25478863633. The next prime is 25478863643. The reversal of 25478863641 is 14636887452.

It is a happy number.

The square root of 25478863641 is 159621.

It is a perfect power (a square), and thus also a powerful number.

25478863641 is a `hidden beast` number, since 25 + 478 + 86 + 36 + 41 = 666.

It is not a de Polignac number, because 25478863641 - 2³ = 25478863633 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (25478863643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 36872106 + ... + 36872796.

Almost surely, 2^25478863641 is an apocalyptic number.

25478863641 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

25478863641 is the 159621-st square number.

25478863641 is the 79811-st centered octagonal number.

It is an amenable number.

25478863641 is a deficient number, since it is larger than the sum of its proper divisors (21646520028).

25478863641 is an equidigital number, since it uses as much as digits as its factorization.

25478863641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1424 (or 712 counting only the distinct ones).

The product of its digits is 7741440, while the sum is 54.

The spelling of 25478863641 in words is "twenty-five billion, four hundred seventy-eight million, eight hundred sixty-three thousand, six hundred forty-one".