1565720243 has 2 divisors, whose sum is σ = 1565720244. Its totient is φ = 1565720242.

The previous prime is 1565720227. The next prime is 1565720249. The reversal of 1565720243 is 3420275651.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1565720243 - 2⁴ = 1565720227 is a prime.

It is not a weakly prime, because it can be changed into another prime (1565720249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 782860121 + 782860122.

It is an arithmetic number, because the mean of its divisors is an integer number (782860122).

Almost surely, 2^1565720243 is an apocalyptic number.

1565720243 is a deficient number, since it is larger than the sum of its proper divisors (1).

1565720243 is an equidigital number, since it uses as much as digits as its factorization.

1565720243 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 50400, while the sum is 35.

The square root of 1565720243 is about 39569.1829963673. The cubic root of 1565720243 is about 1161.1938370589.

Adding to 1565720243 its reverse (3420275651), we get a palindrome (4985995894).

The spelling of 1565720243 in words is "one billion, five hundred sixty-five million, seven hundred twenty thousand, two hundred forty-three".