1939813 has 4 divisors (see below), whose sum is σ = 1942720. Its totient is φ = 1936908.

The previous prime is 1939801. The next prime is 1939837. The reversal of 1939813 is 3189391.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1939813 is a prime.

It is a Duffinian number.

1939813 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1939313) 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, 106 + ... + 1972.

It is an arithmetic number, because the mean of its divisors is an integer number (485680).

2^1939813 is an apocalyptic number.

It is an amenable number.

1939813 is a deficient number, since it is larger than the sum of its proper divisors (2907).

1939813 is a wasteful number, since it uses less digits than its factorization.

1939813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2906.

The product of its digits is 5832, while the sum is 34.

The square root of 1939813 is about 1392.7716970128. The cubic root of 1939813 is about 124.7153630129.

The spelling of 1939813 in words is "one million, nine hundred thirty-nine thousand, eight hundred thirteen".