378836431666 has 64 divisors (see below), whose sum is σ = 721599528960. Its totient is φ = 144874152000.

The previous prime is 378836431661. The next prime is 378836431681. The reversal of 378836431666 is 666134638873.

It is a happy number.

It is a Smith number, since the sum of its digits (61) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (61).

It is not an unprimeable number, because it can be changed into a prime (378836431661) 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 31 ways as a sum of consecutive naturals, for example, 4457631 + ... + 4541821.

It is an arithmetic number, because the mean of its divisors is an integer number (11274992640).

Almost surely, 2^378836431666 is an apocalyptic number.

378836431666 is a deficient number, since it is larger than the sum of its proper divisors (342763097294).

378836431666 is a wasteful number, since it uses less digits than its factorization.

378836431666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84751.

The product of its digits is 62705664, while the sum is 61.

The spelling of 378836431666 in words is "three hundred seventy-eight billion, eight hundred thirty-six million, four hundred thirty-one thousand, six hundred sixty-six".