87060993721 has 9 divisors (see below), whose sum is σ = 94277300781. Its totient is φ = 80360453472.

The previous prime is 87060993713. The next prime is 87060993749. The reversal of 87060993721 is 12739906078.

The square root of 87060993721 is 295061.

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

It can be written as a sum of positive squares in 4 ways, for example, as 71149694121 + 15911299600 = 266739^2 + 126140^2 .

It is not a de Polignac number, because 87060993721 - 2³ = 87060993713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (87060993781) 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 8 ways as a sum of consecutive naturals, for example, 3824445 + ... + 3847141.

Almost surely, 2^87060993721 is an apocalyptic number.

87060993721 is the 295061-st square number.

87060993721 is the 147531-st centered octagonal number.

It is an amenable number.

87060993721 is a deficient number, since it is larger than the sum of its proper divisors (7216307060).

87060993721 is an frugal number, since it uses more digits than its factorization.

87060993721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45420 (or 22710 counting only the distinct ones).

The product of its (nonzero) digits is 1143072, while the sum is 52.

The spelling of 87060993721 in words is "eighty-seven billion, sixty million, nine hundred ninety-three thousand, seven hundred twenty-one".