378681531638 has 16 divisors (see below), whose sum is σ = 616104531504. Its totient is φ = 173856656640.

The previous prime is 378681531623. The next prime is 378681531691. The reversal of 378681531638 is 836135186873.

It is a happy number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 135824120 + ... + 135826907.

It is an arithmetic number, because the mean of its divisors is an integer number (38506533219).

Almost surely, 2^378681531638 is an apocalyptic number.

378681531638 is a deficient number, since it is larger than the sum of its proper divisors (237422999866).

378681531638 is a wasteful number, since it uses less digits than its factorization.

378681531638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 271651087.

The product of its digits is 17418240, while the sum is 59.

The spelling of 378681531638 in words is "three hundred seventy-eight billion, six hundred eighty-one million, five hundred thirty-one thousand, six hundred thirty-eight".