87130961021 has 4 divisors (see below), whose sum is σ = 93833342652. Its totient is φ = 80428579392.

The previous prime is 87130960933. The next prime is 87130961039. The reversal of 87130961021 is 12016903178.

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 23712612121 + 63418348900 = 153989^2 + 251830^2 .

It is a cyclic number.

It is not a de Polignac number, because 87130961021 - 2¹⁰ = 87130959997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87130961051) 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, 3351190796 + ... + 3351190821.

It is an arithmetic number, because the mean of its divisors is an integer number (23458335663).

Almost surely, 2^87130961021 is an apocalyptic number.

It is an amenable number.

87130961021 is a deficient number, since it is larger than the sum of its proper divisors (6702381631).

87130961021 is a wasteful number, since it uses less digits than its factorization.

87130961021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6702381630.

The product of its (nonzero) digits is 18144, while the sum is 38.

The spelling of 87130961021 in words is "eighty-seven billion, one hundred thirty million, nine hundred sixty-one thousand, twenty-one".