378861665545 has 12 divisors (see below), whose sum is σ = 499721668740. Its totient is φ = 275535756320.

The previous prime is 378861665531. The next prime is 378861665579. The reversal of 378861665545 is 545566168873.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 218391720976 + 160469944569 = 467324^2 + 400587^2 .

It is not a de Polignac number, because 378861665545 - 2¹³ = 378861657353 is a prime.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 313108210 + ... + 313109419.

It is an arithmetic number, because the mean of its divisors is an integer number (41643472395).

Almost surely, 2^378861665545 is an apocalyptic number.

It is an amenable number.

378861665545 is a deficient number, since it is larger than the sum of its proper divisors (120860003195).

378861665545 is a wasteful number, since it uses less digits than its factorization.

378861665545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 626217656 (or 626217645 counting only the distinct ones).

The product of its digits is 145152000, while the sum is 64.

The spelling of 378861665545 in words is "three hundred seventy-eight billion, eight hundred sixty-one million, six hundred sixty-five thousand, five hundred forty-five".