215541520423111 has 2 divisors, whose sum is σ = 215541520423112. Its totient is φ = 215541520423110.

The previous prime is 215541520423081. The next prime is 215541520423121. The reversal of 215541520423111 is 111324025145512.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 215541520423111 - 2⁵ = 215541520423079 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215541520423121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107770760211555 + 107770760211556.

It is an arithmetic number, because the mean of its divisors is an integer number (107770760211556).

Almost surely, 2^{215541520423111} is an apocalyptic number.

215541520423111 is a deficient number, since it is larger than the sum of its proper divisors (1).

215541520423111 is an equidigital number, since it uses as much as digits as its factorization.

215541520423111 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48000, while the sum is 37.

Adding to 215541520423111 its reverse (111324025145512), we get a palindrome (326865545568623).

The spelling of 215541520423111 in words is "two hundred fifteen trillion, five hundred forty-one billion, five hundred twenty million, four hundred twenty-three thousand, one hundred eleven".