99986531 has 24 divisors (see below), whose sum is σ = 110605824. Its totient is φ = 90301680.

The previous prime is 99986527. The next prime is 99986539. The reversal of 99986531 is 13568999.

It is not a de Polignac number, because 99986531 - 2² = 99986527 is a prime.

It is a super-2 number, since 2×99986531² = 19994612762827922, which contains 22 as substring.

It is a Smith number, since the sum of its digits (50) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 99986531.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99986539) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1204616 + ... + 1204698.

It is an arithmetic number, because the mean of its divisors is an integer number (4608576).

Almost surely, 2^99986531 is an apocalyptic number.

99986531 is a deficient number, since it is larger than the sum of its proper divisors (10619293).

99986531 is a wasteful number, since it uses less digits than its factorization.

99986531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 239 (or 220 counting only the distinct ones).

The product of its digits is 524880, while the sum is 50.

The square root of 99986531 is about 9999.3265273217. The cubic root of 99986531 is about 464.1380432389.

The spelling of 99986531 in words is "ninety-nine million, nine hundred eighty-six thousand, five hundred thirty-one".