1321361537 has 4 divisors (see below), whose sum is σ = 1321836756. Its totient is φ = 1320886320.

The previous prime is 1321361527. The next prime is 1321361557. The reversal of 1321361537 is 7351631231.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 776792641 + 544568896 = 27871^2 + 23336^2 .

It is a cyclic number.

It is not a de Polignac number, because 1321361537 - 2⁶ = 1321361473 is a prime.

It is a super-2 number, since 2×1321361537² = 3491992622926004738, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1321361527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 233414 + ... + 239007.

It is an arithmetic number, because the mean of its divisors is an integer number (330459189).

Almost surely, 2^1321361537 is an apocalyptic number.

It is an amenable number.

1321361537 is a deficient number, since it is larger than the sum of its proper divisors (475219).

1321361537 is an equidigital number, since it uses as much as digits as its factorization.

1321361537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 475218.

The product of its digits is 11340, while the sum is 32.

The square root of 1321361537 is about 36350.5369561441. The cubic root of 1321361537 is about 1097.3383408372.

Adding to 1321361537 its reverse (7351631231), we get a palindrome (8672992768).

The spelling of 1321361537 in words is "one billion, three hundred twenty-one million, three hundred sixty-one thousand, five hundred thirty-seven".