1321199977 has 2 divisors, whose sum is σ = 1321199978. Its totient is φ = 1321199976.

The previous prime is 1321199947. The next prime is 1321200047. The reversal of 1321199977 is 7799911231.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1268143321 + 53056656 = 35611^2 + 7284^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1321199977 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1321199977.

It is not a weakly prime, because it can be changed into another prime (1321199947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660599988 + 660599989.

It is an arithmetic number, because the mean of its divisors is an integer number (660599989).

Almost surely, 2^1321199977 is an apocalyptic number.

It is an amenable number.

1321199977 is a deficient number, since it is larger than the sum of its proper divisors (1).

1321199977 is an equidigital number, since it uses as much as digits as its factorization.

1321199977 is an evil number, because the sum of its binary digits is even.

The product of its digits is 214326, while the sum is 49.

The square root of 1321199977 is about 36348.3146376830. The cubic root of 1321199977 is about 1097.2936159572.

The spelling of 1321199977 in words is "one billion, three hundred twenty-one million, one hundred ninety-nine thousand, nine hundred seventy-seven".