815787541 has 2 divisors, whose sum is σ = 815787542. Its totient is φ = 815787540.

The previous prime is 815787509. The next prime is 815787547. The reversal of 815787541 is 145787518.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 743707441 + 72080100 = 27271^2 + 8490^2 .

It is a cyclic number.

It is not a de Polignac number, because 815787541 - 2⁵ = 815787509 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 815787491 and 815787500.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (815787547) 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, 407893770 + 407893771.

It is an arithmetic number, because the mean of its divisors is an integer number (407893771).

Almost surely, 2^815787541 is an apocalyptic number.

It is an amenable number.

815787541 is a deficient number, since it is larger than the sum of its proper divisors (1).

815787541 is an equidigital number, since it uses as much as digits as its factorization.

815787541 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 313600, while the sum is 46.

The square root of 815787541 is about 28561.9946957491. The cubic root of 815787541 is about 934.3846374639.

The spelling of 815787541 in words is "eight hundred fifteen million, seven hundred eighty-seven thousand, five hundred forty-one".