1930891 has 4 divisors (see below), whose sum is σ = 1944000. Its totient is φ = 1917784.

The previous prime is 1930883. The next prime is 1930927. The reversal of 1930891 is 1980391.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1980391 = 7 ⋅282913.

It is a cyclic number.

It is not a de Polignac number, because 1930891 - 2³ = 1930883 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1930801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6331 + ... + 6628.

It is an arithmetic number, because the mean of its divisors is an integer number (486000).

2^1930891 is an apocalyptic number.

1930891 is a deficient number, since it is larger than the sum of its proper divisors (13109).

1930891 is a wasteful number, since it uses less digits than its factorization.

1930891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13108.

The product of its (nonzero) digits is 1944, while the sum is 31.

The square root of 1930891 is about 1389.5650398596. The cubic root of 1930891 is about 124.5238633204.

The spelling of 1930891 in words is "one million, nine hundred thirty thousand, eight hundred ninety-one".