215987671 has 2 divisors, whose sum is σ = 215987672. Its totient is φ = 215987670.

The previous prime is 215987657. The next prime is 215987677. The reversal of 215987671 is 176789512.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 215987671 - 2⁷ = 215987543 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215987677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107993835 + 107993836.

It is an arithmetic number, because the mean of its divisors is an integer number (107993836).

Almost surely, 2^215987671 is an apocalyptic number.

215987671 is a deficient number, since it is larger than the sum of its proper divisors (1).

215987671 is an equidigital number, since it uses as much as digits as its factorization.

215987671 is an evil number, because the sum of its binary digits is even.

The product of its digits is 211680, while the sum is 46.

The square root of 215987671 is about 14696.5190096158. The cubic root of 215987671 is about 599.9885840421.

The spelling of 215987671 in words is "two hundred fifteen million, nine hundred eighty-seven thousand, six hundred seventy-one".