1156661563 has 2 divisors, whose sum is σ = 1156661564. Its totient is φ = 1156661562.

The previous prime is 1156661557. The next prime is 1156661579. The reversal of 1156661563 is 3651666511.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1156661563 - 2⁵ = 1156661531 is a prime.

It is not a weakly prime, because it can be changed into another prime (1156661503) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 578330781 + 578330782.

It is an arithmetic number, because the mean of its divisors is an integer number (578330782).

Almost surely, 2^1156661563 is an apocalyptic number.

1156661563 is a deficient number, since it is larger than the sum of its proper divisors (1).

1156661563 is an equidigital number, since it uses as much as digits as its factorization.

1156661563 is an evil number, because the sum of its binary digits is even.

The product of its digits is 97200, while the sum is 40.

The square root of 1156661563 is about 34009.7274761207. The cubic root of 1156661563 is about 1049.7086305675.

The spelling of 1156661563 in words is "one billion, one hundred fifty-six million, six hundred sixty-one thousand, five hundred sixty-three".