1321545531 has 16 divisors (see below), whose sum is σ = 1861207040. Its totient is φ = 832779360.

The previous prime is 1321545527. The next prime is 1321545553. The reversal of 1321545531 is 1355451231.

It is not a de Polignac number, because 1321545531 - 2² = 1321545527 is a prime.

It is a super-2 number, since 2×1321545531² = 3492965181012143922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1321545521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 161236 + ... + 169233.

It is an arithmetic number, because the mean of its divisors is an integer number (116325440).

Almost surely, 2^1321545531 is an apocalyptic number.

1321545531 is a deficient number, since it is larger than the sum of its proper divisors (539661509).

1321545531 is a wasteful number, since it uses less digits than its factorization.

1321545531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 330546.

The product of its digits is 9000, while the sum is 30.

The square root of 1321545531 is about 36353.0676972384. The cubic root of 1321545531 is about 1097.3892717127.

Adding to 1321545531 its reverse (1355451231), we get a palindrome (2676996762).

The spelling of 1321545531 in words is "one billion, three hundred twenty-one million, five hundred forty-five thousand, five hundred thirty-one".