1565380081 has 2 divisors, whose sum is σ = 1565380082. Its totient is φ = 1565380080.

The previous prime is 1565380079. The next prime is 1565380087. The reversal of 1565380081 is 1800835651.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1364194225 + 201185856 = 36935^2 + 14184^2 .

It is an emirp because it is prime and its reverse (1800835651) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1565380081 - 2¹ = 1565380079 is a prime.

It is a super-2 number, since 2×1565380081² = 4900829595983133122, which contains 22 as substring.

Together with 1565380079, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 1565380081.

It is not a weakly prime, because it can be changed into another prime (1565380087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 782690040 + 782690041.

It is an arithmetic number, because the mean of its divisors is an integer number (782690041).

Almost surely, 2^1565380081 is an apocalyptic number.

It is an amenable number.

1565380081 is a deficient number, since it is larger than the sum of its proper divisors (1).

1565380081 is an equidigital number, since it uses as much as digits as its factorization.

1565380081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 28800, while the sum is 37.

The square root of 1565380081 is about 39564.8844431524. The cubic root of 1565380081 is about 1161.1097388878.

The spelling of 1565380081 in words is "one billion, five hundred sixty-five million, three hundred eighty thousand, eighty-one".