87278993 has 2 divisors, whose sum is σ = 87278994. Its totient is φ = 87278992.

The previous prime is 87278987. The next prime is 87279011. The reversal of 87278993 is 39987278.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 56896849 + 30382144 = 7543^2 + 5512^2 .

It is a cyclic number.

It is not a de Polignac number, because 87278993 - 2⁶ = 87278929 is a prime.

It is not a weakly prime, because it can be changed into another prime (87278903) 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, 43639496 + 43639497.

It is an arithmetic number, because the mean of its divisors is an integer number (43639497).

Almost surely, 2^87278993 is an apocalyptic number.

It is an amenable number.

87278993 is a deficient number, since it is larger than the sum of its proper divisors (1).

87278993 is an equidigital number, since it uses as much as digits as its factorization.

87278993 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1524096, while the sum is 53.

The square root of 87278993 is about 9342.3226769364. The cubic root of 87278993 is about 443.5779085919.

The spelling of 87278993 in words is "eighty-seven million, two hundred seventy-eight thousand, nine hundred ninety-three".