86391507821 has 8 divisors (see below), whose sum is σ = 87172179360. Its totient is φ = 85613110128.

The previous prime is 86391507781. The next prime is 86391507859. The reversal of 86391507821 is 12870519368.

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 86391507821 - 2¹⁴ = 86391491437 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 86391507821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (86391507121) 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, 492086 + ... + 644151.

It is an arithmetic number, because the mean of its divisors is an integer number (10896522420).

Almost surely, 2^86391507821 is an apocalyptic number.

It is an amenable number.

86391507821 is a deficient number, since it is larger than the sum of its proper divisors (780671539).

86391507821 is a wasteful number, since it uses less digits than its factorization.

86391507821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1136923.

The product of its (nonzero) digits is 725760, while the sum is 50.

The spelling of 86391507821 in words is "eighty-six billion, three hundred ninety-one million, five hundred seven thousand, eight hundred twenty-one".