1538561641 has 2 divisors, whose sum is σ = 1538561642. Its totient is φ = 1538561640.

The previous prime is 1538561617. The next prime is 1538561653. The reversal of 1538561641 is 1461658351.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 820536025 + 718025616 = 28645^2 + 26796^2 .

It is a cyclic number.

It is not a de Polignac number, because 1538561641 - 2¹¹ = 1538559593 is a prime.

It is a super-2 number, since 2×1538561641² = 4734343846313225762, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1538561594 and 1538561603.

It is not a weakly prime, because it can be changed into another prime (1538561611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 769280820 + 769280821.

It is an arithmetic number, because the mean of its divisors is an integer number (769280821).

Almost surely, 2^1538561641 is an apocalyptic number.

It is an amenable number.

1538561641 is a deficient number, since it is larger than the sum of its proper divisors (1).

1538561641 is an equidigital number, since it uses as much as digits as its factorization.

1538561641 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 86400, while the sum is 40.

The square root of 1538561641 is about 39224.5030688727. The cubic root of 1538561641 is about 1154.4407107081.

The spelling of 1538561641 in words is "one billion, five hundred thirty-eight million, five hundred sixty-one thousand, six hundred forty-one".