1491783431 has 4 divisors (see below), whose sum is σ = 1523523552. Its totient is φ = 1460043312.

The previous prime is 1491783413. The next prime is 1491783437. The reversal of 1491783431 is 1343871941.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1343871941 = 3533 ⋅380377.

It is a cyclic number.

It is not a de Polignac number, because 1491783431 - 2¹⁰ = 1491782407 is a prime.

It is a super-2 number, since 2×1491783431² = 4450835610012263522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1491783437) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15869990 + ... + 15870083.

It is an arithmetic number, because the mean of its divisors is an integer number (380880888).

Almost surely, 2^1491783431 is an apocalyptic number.

1491783431 is a deficient number, since it is larger than the sum of its proper divisors (31740121).

1491783431 is an equidigital number, since it uses as much as digits as its factorization.

1491783431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31740120.

The product of its digits is 72576, while the sum is 41.

The square root of 1491783431 is about 38623.6123504780. The cubic root of 1491783431 is about 1142.6202759352.

The spelling of 1491783431 in words is "one billion, four hundred ninety-one million, seven hundred eighty-three thousand, four hundred thirty-one".