87123126636529 has 27 divisors (see below), whose sum is σ = 89099589284779. Its totient is φ = 85190088001760.

The previous prime is 87123126636521. The next prime is 87123126636641. The reversal of 87123126636529 is 92563662132178.

The square root of 87123126636529 is 9333977.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 58876877958129 + 28246248678400 = 7673127^2 + 5314720^2 .

It is not a de Polignac number, because 87123126636529 - 2³ = 87123126636521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (87123126636521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 154748004402 + ... + 154748004964.

Almost surely, 2^{87123126636529} is an apocalyptic number.

87123126636529 is the 9333977-th square number.

87123126636529 is the 4666989-th centered octagonal number.

It is an amenable number.

87123126636529 is a deficient number, since it is larger than the sum of its proper divisors (1976462648250).

87123126636529 is an frugal number, since it uses more digits than its factorization.

87123126636529 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1806 (or 903 counting only the distinct ones).

The product of its digits is 39191040, while the sum is 61.

The spelling of 87123126636529 in words is "eighty-seven trillion, one hundred twenty-three billion, one hundred twenty-six million, six hundred thirty-six thousand, five hundred twenty-nine".