25401656205 has 48 divisors (see below), whose sum is σ = 45982235520. Its totient is φ = 12947704704.

The previous prime is 25401656197. The next prime is 25401656209. The reversal of 25401656205 is 50265610452.

25401656205 is a `hidden beast` number, since 25 + 4 + 0 + 1 + 6 + 5 + 620 + 5 = 666.

It is not a de Polignac number, because 25401656205 - 2³ = 25401656197 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 25401656205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25401656209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1312086 + ... + 1331304.

It is an arithmetic number, because the mean of its divisors is an integer number (957963240).

Almost surely, 2^25401656205 is an apocalyptic number.

It is an amenable number.

25401656205 is a deficient number, since it is larger than the sum of its proper divisors (20580579315).

25401656205 is a wasteful number, since it uses less digits than its factorization.

25401656205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20530 (or 20527 counting only the distinct ones).

The product of its (nonzero) digits is 72000, while the sum is 36.

The spelling of 25401656205 in words is "twenty-five billion, four hundred one million, six hundred fifty-six thousand, two hundred five".