87222181 has 2 divisors, whose sum is σ = 87222182. Its totient is φ = 87222180.

The previous prime is 87222139. The next prime is 87222193. The reversal of 87222181 is 18122278.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 60699681 + 26522500 = 7791^2 + 5150^2 .

It is a cyclic number.

It is not a de Polignac number, because 87222181 - 2⁹ = 87221669 is a prime.

It is a super-2 number, since 2×87222181² = 15215417716793522, which contains 22 as substring.

It is a Chen prime.

It is equal to p_5065348 and since 87222181 and 5065348 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87222481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43611090 + 43611091.

It is an arithmetic number, because the mean of its divisors is an integer number (43611091).

Almost surely, 2^87222181 is an apocalyptic number.

It is an amenable number.

87222181 is a deficient number, since it is larger than the sum of its proper divisors (1).

87222181 is an equidigital number, since it uses as much as digits as its factorization.

87222181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3584, while the sum is 31.

The square root of 87222181 is about 9339.2816104880. The cubic root of 87222181 is about 443.4816425179.

The spelling of 87222181 in words is "eighty-seven million, two hundred twenty-two thousand, one hundred eighty-one".