1321115731 has 8 divisors (see below), whose sum is σ = 1439882640. Its totient is φ = 1204797792.

The previous prime is 1321115729. The next prime is 1321115737. The reversal of 1321115731 is 1375111231.

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 1321115731 - 2¹ = 1321115729 is a prime.

It is a super-2 number, since 2×1321115731² = 3490693549391328722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1321115696 and 1321115705.

It is not an unprimeable number, because it can be changed into a prime (1321115737) 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, 611116 + ... + 613273.

It is an arithmetic number, because the mean of its divisors is an integer number (179985330).

Almost surely, 2^1321115731 is an apocalyptic number.

1321115731 is a deficient number, since it is larger than the sum of its proper divisors (118766909).

1321115731 is a wasteful number, since it uses less digits than its factorization.

1321115731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1224485.

The product of its digits is 630, while the sum is 25.

The square root of 1321115731 is about 36347.1557484214. The cubic root of 1321115731 is about 1097.2702925733.

Adding to 1321115731 its reverse (1375111231), we get a palindrome (2696226962).

The spelling of 1321115731 in words is "one billion, three hundred twenty-one million, one hundred fifteen thousand, seven hundred thirty-one".