1891013 has 4 divisors (see below), whose sum is σ = 1990560. Its totient is φ = 1791468.

The previous prime is 1891007. The next prime is 1891027. The reversal of 1891013 is 3101981.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 3101981 = 239 ⋅12979.

It is a cyclic number.

It is not a de Polignac number, because 1891013 - 2⁴ = 1890997 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1891013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1891073) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49745 + ... + 49782.

It is an arithmetic number, because the mean of its divisors is an integer number (497640).

2^1891013 is an apocalyptic number.

It is an amenable number.

1891013 is a deficient number, since it is larger than the sum of its proper divisors (99547).

1891013 is an equidigital number, since it uses as much as digits as its factorization.

1891013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99546.

The product of its (nonzero) digits is 216, while the sum is 23.

The square root of 1891013 is about 1375.1410836711. The cubic root of 1891013 is about 123.6606442660.

Adding to 1891013 its reverse (3101981), we get a palindrome (4992994).

The spelling of 1891013 in words is "one million, eight hundred ninety-one thousand, thirteen".