1320731 has 2 divisors, whose sum is σ = 1320732. Its totient is φ = 1320730.

The previous prime is 1320727. The next prime is 1320749. The reversal of 1320731 is 1370231.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1320731 - 2² = 1320727 is a prime.

It is a super-2 number, since 2×1320731² = 3488660748722, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1320721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660365 + 660366.

It is an arithmetic number, because the mean of its divisors is an integer number (660366).

2^1320731 is an apocalyptic number.

1320731 is a deficient number, since it is larger than the sum of its proper divisors (1).

1320731 is an equidigital number, since it uses as much as digits as its factorization.

1320731 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 126, while the sum is 17.

The square root of 1320731 is about 1149.2306121923. The cubic root of 1320731 is about 109.7163767744.

Adding to 1320731 its reverse (1370231), we get a palindrome (2690962).

The spelling of 1320731 in words is "one million, three hundred twenty thousand, seven hundred thirty-one".