1491931 has 4 divisors (see below), whose sum is σ = 1705072. Its totient is φ = 1278792.

The previous prime is 1491929. The next prime is 1491943. The reversal of 1491931 is 1391941.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1491931 - 2¹ = 1491929 is a prime.

It is a super-2 number, since 2×1491931² = 4451716217522, which contains 22 as substring.

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 1491931.

It is not an unprimeable number, because it can be changed into a prime (1491911) 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, 106560 + ... + 106573.

It is an arithmetic number, because the mean of its divisors is an integer number (426268).

2^1491931 is an apocalyptic number.

1491931 is a deficient number, since it is larger than the sum of its proper divisors (213141).

1491931 is an equidigital number, since it uses as much as digits as its factorization.

1491931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213140.

The product of its digits is 972, while the sum is 28.

The square root of 1491931 is about 1221.4462738901. The cubic root of 1491931 is about 114.2657951147.

It can be divided in two parts, 149 and 1931, that added together give a triangular number (2080 = T₆₄).

The spelling of 1491931 in words is "one million, four hundred ninety-one thousand, nine hundred thirty-one".