2158136738 has 4 divisors (see below), whose sum is σ = 3237205110. Its totient is φ = 1079068368.

The previous prime is 2158136677. The next prime is 2158136797. The reversal of 2158136738 is 8376318512.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 1982653729 + 175483009 = 44527^2 + 13247^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 539534183 + ... + 539534186.

Almost surely, 2^2158136738 is an apocalyptic number.

2158136738 is a deficient number, since it is larger than the sum of its proper divisors (1079068372).

2158136738 is a wasteful number, since it uses less digits than its factorization.

2158136738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1079068371.

The product of its digits is 241920, while the sum is 44.

The square root of 2158136738 is about 46455.7503222152. The cubic root of 2158136738 is about 1292.2890148423.

The spelling of 2158136738 in words is "two billion, one hundred fifty-eight million, one hundred thirty-six thousand, seven hundred thirty-eight".