1891142438 has 8 divisors (see below), whose sum is σ = 2837128680. Its totient is φ = 945432880.

The previous prime is 1891142417. The next prime is 1891142443. The reversal of 1891142438 is 8342411981.

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

It is a junction number, because it is equal to n+sod(n) for n = 1891142395 and 1891142404.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 51143 + ... + 79986.

It is an arithmetic number, because the mean of its divisors is an integer number (354641085).

Almost surely, 2^1891142438 is an apocalyptic number.

1891142438 is a deficient number, since it is larger than the sum of its proper divisors (945986242).

1891142438 is a wasteful number, since it uses less digits than its factorization.

1891142438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138342.

The product of its digits is 55296, while the sum is 41.

The square root of 1891142438 is about 43487.2675389015. The cubic root of 1891142438 is about 1236.6346568518.

The spelling of 1891142438 in words is "one billion, eight hundred ninety-one million, one hundred forty-two thousand, four hundred thirty-eight".