1321447769 has 2 divisors, whose sum is σ = 1321447770. Its totient is φ = 1321447768.

The previous prime is 1321447763. The next prime is 1321447807. The reversal of 1321447769 is 9677441231.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 876870544 + 444577225 = 29612^2 + 21085^2 .

It is an emirp because it is prime and its reverse (9677441231) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1321447769 - 2²⁰ = 1320399193 is a prime.

It is a super-2 number, since 2×1321447769² = 3492448412390154722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1321447763) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660723884 + 660723885.

It is an arithmetic number, because the mean of its divisors is an integer number (660723885).

Almost surely, 2^1321447769 is an apocalyptic number.

It is an amenable number.

1321447769 is a deficient number, since it is larger than the sum of its proper divisors (1).

1321447769 is an equidigital number, since it uses as much as digits as its factorization.

1321447769 is an evil number, because the sum of its binary digits is even.

The product of its digits is 254016, while the sum is 44.

The square root of 1321447769 is about 36351.7230540727. The cubic root of 1321447769 is about 1097.3622110697.

The spelling of 1321447769 in words is "one billion, three hundred twenty-one million, four hundred forty-seven thousand, seven hundred sixty-nine".