87717901639681 has 8 divisors (see below), whose sum is σ = 88412403614184. Its totient is φ = 87026117873280.

The previous prime is 87717901639609. The next prime is 87717901639699. The reversal of 87717901639681 is 18693610971778.

It can be written as a sum of positive squares in 4 ways, for example, as 701840142081 + 87016061497600 = 837759^2 + 9328240^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 87717901639681 - 2¹⁹ = 87717901115393 is a prime.

It is a super-2 number, since 2×87717901639681² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (87717901639481) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 679487230 + ... + 679616311.

It is an arithmetic number, because the mean of its divisors is an integer number (11051550451773).

Almost surely, 2^{87717901639681} is an apocalyptic number.

It is an amenable number.

87717901639681 is a deficient number, since it is larger than the sum of its proper divisors (694501974503).

87717901639681 is a wasteful number, since it uses less digits than its factorization.

87717901639681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1359104051.

The product of its (nonzero) digits is 192036096, while the sum is 73.

The spelling of 87717901639681 in words is "eighty-seven trillion, seven hundred seventeen billion, nine hundred one million, six hundred thirty-nine thousand, six hundred eighty-one".