86921721942841 has 4 divisors (see below), whose sum is σ = 86931670643572. Its totient is φ = 86911773242112.

The previous prime is 86921721942833. The next prime is 86921721942851. The reversal of 86921721942841 is 14824912712968.

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 56910728966400 + 30010992976441 = 7543920^2 + 5478229^2 .

It is a cyclic number.

It is not a de Polignac number, because 86921721942841 - 2³ = 86921721942833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (86921721942851) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4974337260 + ... + 4974354733.

It is an arithmetic number, because the mean of its divisors is an integer number (21732917660893).

Almost surely, 2^{86921721942841} is an apocalyptic number.

It is an amenable number.

86921721942841 is a deficient number, since it is larger than the sum of its proper divisors (9948700731).

86921721942841 is an equidigital number, since it uses as much as digits as its factorization.

86921721942841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9948700730.

The product of its digits is 27869184, while the sum is 64.

The spelling of 86921721942841 in words is "eighty-six trillion, nine hundred twenty-one billion, seven hundred twenty-one million, nine hundred forty-two thousand, eight hundred forty-one".