20256131335545 has 192 divisors, whose sum is σ = 46667439636480. Its totient is φ = 7897564882944.

The previous prime is 20256131335543. The next prime is 20256131335607. The reversal of 20256131335545 is 54553313165202.

20256131335545 is a `hidden beast` number, since 2 + 0 + 2 + 5 + 61 + 3 + 1 + 33 + 554 + 5 = 666.

It is not a de Polignac number, because 20256131335545 - 2¹ = 20256131335543 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 20256131335545.

It is not an unprimeable number, because it can be changed into a prime (20256131335543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 1987849 + ... + 6668118.

It is an arithmetic number, because the mean of its divisors is an integer number (243059581440).

Almost surely, 2^{20256131335545} is an apocalyptic number.

It is an amenable number.

20256131335545 is an abundant number, since it is smaller than the sum of its proper divisors (26411308300935).

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

20256131335545 is a wasteful number, since it uses less digits than its factorization.

20256131335545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8656044 (or 8656041 counting only the distinct ones).

The product of its (nonzero) digits is 1620000, while the sum is 45.

The spelling of 20256131335545 in words is "twenty trillion, two hundred fifty-six billion, one hundred thirty-one million, three hundred thirty-five thousand, five hundred forty-five".