1638985434394 has 32 divisors (see below), whose sum is σ = 3198381520896. Its totient is φ = 610802023920.

The previous prime is 1638985434391. The next prime is 1638985434413. The reversal of 1638985434394 is 4934345898361.

It is not an unprimeable number, because it can be changed into a prime (1638985434391) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 231360862 + ... + 231367945.

It is an arithmetic number, because the mean of its divisors is an integer number (99949422528).

Almost surely, 2^{1638985434394} is an apocalyptic number.

1638985434394 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

1638985434394 is a deficient number, since it is larger than the sum of its proper divisors (1559396086502).

1638985434394 is a wasteful number, since it uses less digits than its factorization.

1638985434394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 462728850.

The product of its digits is 268738560, while the sum is 67.

The spelling of 1638985434394 in words is "one trillion, six hundred thirty-eight billion, nine hundred eighty-five million, four hundred thirty-four thousand, three hundred ninety-four".