919138839 has 8 divisors (see below), whose sum is σ = 1242306672. Its totient is φ = 604365120.

The previous prime is 919138823. The next prime is 919138841. The reversal of 919138839 is 938831919.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 919138839 - 2⁴ = 919138823 is a prime.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 919138791 and 919138800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (919138819) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2098272 + ... + 2098709.

It is an arithmetic number, because the mean of its divisors is an integer number (155288334).

Almost surely, 2^919138839 is an apocalyptic number.

919138839 is a deficient number, since it is larger than the sum of its proper divisors (323167833).

919138839 is a wasteful number, since it uses less digits than its factorization.

919138839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4197057.

The product of its digits is 419904, while the sum is 51.

The square root of 919138839 is about 30317.3026339745. The cubic root of 919138839 is about 972.2852693232.

The spelling of 919138839 in words is "nine hundred nineteen million, one hundred thirty-eight thousand, eight hundred thirty-nine".