1540321 has 2 divisors, whose sum is σ = 1540322. Its totient is φ = 1540320.

The previous prime is 1540309. The next prime is 1540337. The reversal of 1540321 is 1230451.

It is an a-pointer prime, because the next prime (1540337) can be obtained adding 1540321 to its sum of digits (16).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 876096 + 664225 = 936^2 + 815^2 .

It is a cyclic number.

It is not a de Polignac number, because 1540321 - 2⁵ = 1540289 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1540295 and 1540304.

It is not a weakly prime, because it can be changed into another prime (1540621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 770160 + 770161.

It is an arithmetic number, because the mean of its divisors is an integer number (770161).

2^1540321 is an apocalyptic number.

It is an amenable number.

1540321 is a deficient number, since it is larger than the sum of its proper divisors (1).

1540321 is an equidigital number, since it uses as much as digits as its factorization.

1540321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 1540321 is about 1241.0966924458. The cubic root of 1540321 is about 115.4880580846.

Adding to 1540321 its reverse (1230451), we get a palindrome (2770772).

The spelling of 1540321 in words is "one million, five hundred forty thousand, three hundred twenty-one".