87139369 has 2 divisors, whose sum is σ = 87139370. Its totient is φ = 87139368.

The previous prime is 87139361. The next prime is 87139417. The reversal of 87139369 is 96393178.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 72046144 + 15093225 = 8488^2 + 3885^2 .

It is a cyclic number.

It is not a de Polignac number, because 87139369 - 2³ = 87139361 is a prime.

It is a super-2 number, since 2×87139369² = 15186539259436322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (87139361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43569684 + 43569685.

It is an arithmetic number, because the mean of its divisors is an integer number (43569685).

Almost surely, 2^87139369 is an apocalyptic number.

It is an amenable number.

87139369 is a deficient number, since it is larger than the sum of its proper divisors (1).

87139369 is an equidigital number, since it uses as much as digits as its factorization.

87139369 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 244944, while the sum is 46.

The square root of 87139369 is about 9334.8470260631. The cubic root of 87139369 is about 443.3412453912.

The spelling of 87139369 in words is "eighty-seven million, one hundred thirty-nine thousand, three hundred sixty-nine".