1091431 has 8 divisors (see below), whose sum is σ = 1198224. Its totient is φ = 985920.

The previous prime is 1091413. The next prime is 1091443. The reversal of 1091431 is 1341901.

1091431 = 424² + 425² + ... + 429².

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1091431 - 2⁵ = 1091399 is a prime.

It is a super-2 number, since 2×1091431² = 2382443255522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1091399 and 1091408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1091401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3285 + ... + 3601.

It is an arithmetic number, because the mean of its divisors is an integer number (149778).

2^1091431 is an apocalyptic number.

1091431 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1091431 is a deficient number, since it is larger than the sum of its proper divisors (106793).

1091431 is a wasteful number, since it uses less digits than its factorization.

1091431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 641.

The product of its (nonzero) digits is 108, while the sum is 19.

The square root of 1091431 is about 1044.7157508145. The cubic root of 1091431 is about 102.9592637478.

It can be divided in two parts, 109 and 1431, that added together give a triangular number (1540 = T₅₅).

The spelling of 1091431 in words is "one million, ninety-one thousand, four hundred thirty-one".