61440385545 has 128 divisors (see below), whose sum is σ = 136401408000. Its totient is φ = 25492078080.

The previous prime is 61440385529. The next prime is 61440385637. The reversal of 61440385545 is 54558304416.

61440385545 is a `hidden beast` number, since 61 + 4 + 4 + 0 + 38 + 554 + 5 = 666.

It is not a de Polignac number, because 61440385545 - 2⁴ = 61440385529 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 61440385545.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 6845821 + ... + 6854789.

It is an arithmetic number, because the mean of its divisors is an integer number (1065636000).

Almost surely, 2^61440385545 is an apocalyptic number.

It is an amenable number.

61440385545 is an abundant number, since it is smaller than the sum of its proper divisors (74961022455).

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

61440385545 is a wasteful number, since it uses less digits than its factorization.

61440385545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9660 (or 9654 counting only the distinct ones).

The product of its (nonzero) digits is 1152000, while the sum is 45.

It can be divided in two parts, 61440 and 385545, that added together give a triangular number (446985 = T₉₄₅).

The spelling of 61440385545 in words is "sixty-one billion, four hundred forty million, three hundred eighty-five thousand, five hundred forty-five".