1563425581 has 2 divisors, whose sum is σ = 1563425582. Its totient is φ = 1563425580.

The previous prime is 1563425557. The next prime is 1563425603. The reversal of 1563425581 is 1855243651.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1533897225 + 29528356 = 39165^2 + 5434^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1563425581 is a prime.

It is a super-2 number, since 2×1563425581² = 4888599094650375122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1563420581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 781712790 + 781712791.

It is an arithmetic number, because the mean of its divisors is an integer number (781712791).

Almost surely, 2^1563425581 is an apocalyptic number.

It is an amenable number.

1563425581 is a deficient number, since it is larger than the sum of its proper divisors (1).

1563425581 is an equidigital number, since it uses as much as digits as its factorization.

1563425581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 144000, while the sum is 40.

The square root of 1563425581 is about 39540.1767952547. The cubic root of 1563425581 is about 1160.6262920514.

The spelling of 1563425581 in words is "one billion, five hundred sixty-three million, four hundred twenty-five thousand, five hundred eighty-one".