215515556671 has 2 divisors, whose sum is σ = 215515556672. Its totient is φ = 215515556670.

The previous prime is 215515556591. The next prime is 215515556677. The reversal of 215515556671 is 176655515512.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 215515556671 - 2²⁹ = 214978685759 is a prime.

It is a super-2 number, since 2×215515556671² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215515556677) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107757778335 + 107757778336.

It is an arithmetic number, because the mean of its divisors is an integer number (107757778336).

Almost surely, 2^215515556671 is an apocalyptic number.

215515556671 is a deficient number, since it is larger than the sum of its proper divisors (1).

215515556671 is an equidigital number, since it uses as much as digits as its factorization.

215515556671 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1575000, while the sum is 49.

The spelling of 215515556671 in words is "two hundred fifteen billion, five hundred fifteen million, five hundred fifty-six thousand, six hundred seventy-one".