87751681 has 2 divisors, whose sum is σ = 87751682. Its totient is φ = 87751680.

The previous prime is 87751639. The next prime is 87751717. The reversal of 87751681 is 18615778.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 76300225 + 11451456 = 8735^2 + 3384^2 .

It is a cyclic number.

It is not a de Polignac number, because 87751681 - 2¹³ = 87743489 is a prime.

It is a super-2 number, since 2×87751681² = 15400715036651522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (87751981) 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, 43875840 + 43875841.

It is an arithmetic number, because the mean of its divisors is an integer number (43875841).

Almost surely, 2^87751681 is an apocalyptic number.

It is an amenable number.

87751681 is a deficient number, since it is larger than the sum of its proper divisors (1).

87751681 is an equidigital number, since it uses as much as digits as its factorization.

87751681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 94080, while the sum is 43.

The square root of 87751681 is about 9367.5867223101. The cubic root of 87751681 is about 444.3772478247.

The spelling of 87751681 in words is "eighty-seven million, seven hundred fifty-one thousand, six hundred eighty-one".