1321286761 has 8 divisors (see below), whose sum is σ = 1370990600. Its totient is φ = 1272319488.

The previous prime is 1321286753. The next prime is 1321286851. The reversal of 1321286761 is 1676821231.

It can be written as a sum of positive squares in 4 ways, for example, as 82246761 + 1239040000 = 9069^2 + 35200^2 .

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 1321286761 - 2³ = 1321286753 is a prime.

It is a super-2 number, since 2×1321286761² = 3491597409587742242, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a self number, because there is not a number n which added to its sum of digits gives 1321286761.

It is not an unprimeable number, because it can be changed into a prime (1321286741) 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, 180486 + ... + 187663.

It is an arithmetic number, because the mean of its divisors is an integer number (171373825).

Almost surely, 2^1321286761 is an apocalyptic number.

It is an amenable number.

1321286761 is a deficient number, since it is larger than the sum of its proper divisors (49703839).

1321286761 is an equidigital number, since it uses as much as digits as its factorization.

1321286761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 368283.

The product of its digits is 24192, while the sum is 37.

The square root of 1321286761 is about 36349.5084010774. The cubic root of 1321286761 is about 1097.3176409461.

The spelling of 1321286761 in words is "one billion, three hundred twenty-one million, two hundred eighty-six thousand, seven hundred sixty-one".