87172637929 has 4 divisors (see below), whose sum is σ = 93878225476. Its totient is φ = 80467050384.

The previous prime is 87172637891. The next prime is 87172637947. The reversal of 87172637929 is 92973627178.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 57982232025 + 29190405904 = 240795^2 + 170852^2 .

It is a cyclic number.

It is not a de Polignac number, because 87172637929 - 2²¹ = 87170540777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (87172637129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3352793754 + ... + 3352793779.

It is an arithmetic number, because the mean of its divisors is an integer number (23469556369).

Almost surely, 2^87172637929 is an apocalyptic number.

It is an amenable number.

87172637929 is a deficient number, since it is larger than the sum of its proper divisors (6705587547).

87172637929 is a wasteful number, since it uses less digits than its factorization.

87172637929 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6705587546.

The product of its digits is 16003008, while the sum is 61.

The spelling of 87172637929 in words is "eighty-seven billion, one hundred seventy-two million, six hundred thirty-seven thousand, nine hundred twenty-nine".