215750881 has 2 divisors, whose sum is σ = 215750882. Its totient is φ = 215750880.

The previous prime is 215750869. The next prime is 215750903. The reversal of 215750881 is 188057512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 177422400 + 38328481 = 13320^2 + 6191^2 .

It is a cyclic number.

It is not a de Polignac number, because 215750881 - 2⁵ = 215750849 is a prime.

It is a super-2 number, since 2×215750881² = 93096885304552322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 215750881.

It is not a weakly prime, because it can be changed into another prime (215750831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107875440 + 107875441.

It is an arithmetic number, because the mean of its divisors is an integer number (107875441).

Almost surely, 2^215750881 is an apocalyptic number.

It is an amenable number.

215750881 is a deficient number, since it is larger than the sum of its proper divisors (1).

215750881 is an equidigital number, since it uses as much as digits as its factorization.

215750881 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 22400, while the sum is 37.

The square root of 215750881 is about 14688.4608111265. The cubic root of 215750881 is about 599.7692455246.

The spelling of 215750881 in words is "two hundred fifteen million, seven hundred fifty thousand, eight hundred eighty-one".