86878521 has 16 divisors (see below), whose sum is σ = 134305920. Its totient is φ = 55400400.

The previous prime is 86878499. The next prime is 86878529. The reversal of 86878521 is 12587868.

It is not a de Polignac number, because 86878521 - 2¹⁴ = 86862137 is a prime.

It is a super-2 number, since 2×86878521² = 15095754822294882, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (86878529) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 69330 + ... + 70571.

It is an arithmetic number, because the mean of its divisors is an integer number (8394120).

Almost surely, 2^86878521 is an apocalyptic number.

It is an amenable number.

86878521 is a deficient number, since it is larger than the sum of its proper divisors (47427399).

86878521 is a wasteful number, since it uses less digits than its factorization.

86878521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139933 (or 139927 counting only the distinct ones).

The product of its digits is 215040, while the sum is 45.

The square root of 86878521 is about 9320.8648203909. The cubic root of 86878521 is about 442.8984288500.

The spelling of 86878521 in words is "eighty-six million, eight hundred seventy-eight thousand, five hundred twenty-one".