1939542389 has 4 divisors (see below), whose sum is σ = 1939705440. Its totient is φ = 1939379340.

The previous prime is 1939542383. The next prime is 1939542431. The reversal of 1939542389 is 9832459391.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 9832459391 = 22067 ⋅445573.

It is a cyclic number.

It is not a de Polignac number, because 1939542389 - 2²⁰ = 1938493813 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1939542389.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1939542383) 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 3 ways as a sum of consecutive naturals, for example, 62147 + ... + 87984.

It is an arithmetic number, because the mean of its divisors is an integer number (484926360).

Almost surely, 2^1939542389 is an apocalyptic number.

It is an amenable number.

1939542389 is a deficient number, since it is larger than the sum of its proper divisors (163051).

1939542389 is a wasteful number, since it uses less digits than its factorization.

1939542389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163050.

The product of its digits is 2099520, while the sum is 53.

The square root of 1939542389 is about 44040.2360234366. The cubic root of 1939542389 is about 1247.0956332696.

The spelling of 1939542389 in words is "one billion, nine hundred thirty-nine million, five hundred forty-two thousand, three hundred eighty-nine".