1938638694 has 16 divisors (see below), whose sum is σ = 3878372160. Its totient is φ = 646030440.

The previous prime is 1938638693. The next prime is 1938638729. The reversal of 1938638694 is 4968368391.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1938638693) 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 7 ways as a sum of consecutive naturals, for example, 21624 + ... + 65915.

It is an arithmetic number, because the mean of its divisors is an integer number (242398260).

Almost surely, 2^1938638694 is an apocalyptic number.

1938638694 is an abundant number, since it is smaller than the sum of its proper divisors (1939733466).

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

1938638694 is a wasteful number, since it uses less digits than its factorization.

1938638694 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91235.

The product of its digits is 6718464, while the sum is 57.

The square root of 1938638694 is about 44029.9749488914. The cubic root of 1938638694 is about 1246.9019158969.

The spelling of 1938638694 in words is "one billion, nine hundred thirty-eight million, six hundred thirty-eight thousand, six hundred ninety-four".