1531321 has 8 divisors (see below), whose sum is σ = 1694304. Its totient is φ = 1372320.

The previous prime is 1531303. The next prime is 1531331. The reversal of 1531321 is 1231351.

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 1531321 - 2¹¹ = 1529273 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1531295 and 1531304.

It is not an unprimeable number, because it can be changed into a prime (1531331) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 151 + ... + 1756.

It is an arithmetic number, because the mean of its divisors is an integer number (211788).

2^1531321 is an apocalyptic number.

1531321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1531321 is a deficient number, since it is larger than the sum of its proper divisors (162983).

1531321 is a wasteful number, since it uses less digits than its factorization.

1531321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1991.

The product of its digits is 90, while the sum is 16.

The square root of 1531321 is about 1237.4655550762. The cubic root of 1531321 is about 115.2626887214.

Adding to 1531321 its reverse (1231351), we get a palindrome (2762672).

The spelling of 1531321 in words is "one million, five hundred thirty-one thousand, three hundred twenty-one".