1640379166638 has 16 divisors (see below), whose sum is σ = 3290669993856. Its totient is φ = 545141112120.

The previous prime is 1640379166637. The next prime is 1640379166649. The reversal of 1640379166638 is 8366619730461.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640379166637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 412983706 + ... + 412987677.

It is an arithmetic number, because the mean of its divisors is an integer number (205666874616).

Almost surely, 2^{1640379166638} is an apocalyptic number.

1640379166638 is an abundant number, since it is smaller than the sum of its proper divisors (1650290827218).

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

1640379166638 is a wasteful number, since it uses less digits than its factorization.

1640379166638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 825971719.

The product of its (nonzero) digits is 23514624, while the sum is 60.

The spelling of 1640379166638 in words is "one trillion, six hundred forty billion, three hundred seventy-nine million, one hundred sixty-six thousand, six hundred thirty-eight".