25440421205385 has 12 divisors (see below), whose sum is σ = 44096730089412. Its totient is φ = 13568224642848.

The previous prime is 25440421205341. The next prime is 25440421205387. The reversal of 25440421205385 is 58350212404452.

25440421205385 is a `hidden beast` number, since 2 + 5 + 4 + 40 + 4 + 21 + 205 + 385 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 16719332189184 + 8721089016201 = 4088928^2 + 2953149^2 .

It is not a de Polignac number, because 25440421205385 - 2⁹ = 25440421204873 is a prime.

It is a super-2 number, since 2×25440421205385² (a number of 28 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 565342693453 = 25440421205385 / (2 + 5 + 4 + 4 + 0 + 4 + 2 + 1 + 2 + 0 + 5 + 3 + 8 + 5).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 25440421205385.

It is not an unprimeable number, because it can be changed into a prime (25440421205387) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 282671346682 + ... + 282671346771.

It is an arithmetic number, because the mean of its divisors is an integer number (3674727507451).

Almost surely, 2^{25440421205385} is an apocalyptic number.

It is an amenable number.

25440421205385 is a deficient number, since it is larger than the sum of its proper divisors (18656308884027).

25440421205385 is a wasteful number, since it uses less digits than its factorization.

25440421205385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 565342693464 (or 565342693461 counting only the distinct ones).

The product of its (nonzero) digits is 1536000, while the sum is 45.

The spelling of 25440421205385 in words is "twenty-five trillion, four hundred forty billion, four hundred twenty-one million, two hundred five thousand, three hundred eighty-five".