2138532478 has 4 divisors (see below), whose sum is σ = 3207798720. Its totient is φ = 1069266238.

The previous prime is 2138532397. The next prime is 2138532491. The reversal of 2138532478 is 8742358312.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 534633118 + ... + 534633121.

It is an arithmetic number, because the mean of its divisors is an integer number (801949680).

Almost surely, 2^2138532478 is an apocalyptic number.

2138532478 is a deficient number, since it is larger than the sum of its proper divisors (1069266242).

2138532478 is a wasteful number, since it uses less digits than its factorization.

2138532478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1069266241.

The product of its digits is 322560, while the sum is 43.

The square root of 2138532478 is about 46244.2696774422. The cubic root of 2138532478 is about 1288.3641058588.

The spelling of 2138532478 in words is "two billion, one hundred thirty-eight million, five hundred thirty-two thousand, four hundred seventy-eight".