81025986 has 8 divisors (see below), whose sum is σ = 162051984. Its totient is φ = 27008660.

The previous prime is 81025957. The next prime is 81025999. The reversal of 81025986 is 68952018.

It is a sphenic number, since it is the product of 3 distinct primes.

81025986 is an admirable number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6752160 + ... + 6752171.

It is an arithmetic number, because the mean of its divisors is an integer number (20256498).

Almost surely, 2^81025986 is an apocalyptic number.

81025986 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81025986 is a wasteful number, since it uses less digits than its factorization.

81025986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13504336.

The product of its (nonzero) digits is 34560, while the sum is 39.

The square root of 81025986 is about 9001.4435508978. The cubic root of 81025986 is about 432.7211356480.

It can be divided in two parts, 810 and 25986, that added together give a triangular number (26796 = T₂₃₁).

The spelling of 81025986 in words is "eighty-one million, twenty-five thousand, nine hundred eighty-six".