1891663742 has 4 divisors (see below), whose sum is σ = 2837495616. Its totient is φ = 945831870.

The previous prime is 1891663733. The next prime is 1891663777. The reversal of 1891663742 is 2473661981.

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 polite number, since it can be written as a sum of consecutive naturals, namely, 472915934 + ... + 472915937.

It is an arithmetic number, because the mean of its divisors is an integer number (709373904).

Almost surely, 2^1891663742 is an apocalyptic number.

1891663742 is a deficient number, since it is larger than the sum of its proper divisors (945831874).

1891663742 is an equidigital number, since it uses as much as digits as its factorization.

1891663742 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 945831873.

The product of its digits is 435456, while the sum is 47.

The square root of 1891663742 is about 43493.2608802789. The cubic root of 1891663742 is about 1236.7482748346.

The spelling of 1891663742 in words is "one billion, eight hundred ninety-one million, six hundred sixty-three thousand, seven hundred forty-two".