1289431 has 16 divisors (see below), whose sum is σ = 1548288. Its totient is φ = 1058400.

The previous prime is 1289429. The next prime is 1289447. The reversal of 1289431 is 1349821.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1289431 - 2¹ = 1289429 is a prime.

It is a super-2 number, since 2×1289431² = 3325264607522, 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 1289431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1289401) 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 15 ways as a sum of consecutive naturals, for example, 10090 + ... + 10216.

It is an arithmetic number, because the mean of its divisors is an integer number (96768).

2^1289431 is an apocalyptic number.

1289431 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1289431 is a deficient number, since it is larger than the sum of its proper divisors (258857).

1289431 is a wasteful number, since it uses less digits than its factorization.

1289431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222.

The product of its digits is 1728, while the sum is 28.

The square root of 1289431 is about 1135.5311532494. The cubic root of 1289431 is about 108.8427156650.

It can be divided in two parts, 128 and 9431, that added together give a palindrome (9559).

The spelling of 1289431 in words is "one million, two hundred eighty-nine thousand, four hundred thirty-one".