81085996 has 24 divisors (see below), whose sum is σ = 149688000. Its totient is φ = 38327184.

The previous prime is 81085993. The next prime is 81085999. The reversal of 81085996 is 69958018.

It is an interprime number because it is at equal distance from previous prime (81085993) and next prime (81085999).

It is not an unprimeable number, because it can be changed into a prime (81085993) 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, 49275 + ... + 50893.

It is an arithmetic number, because the mean of its divisors is an integer number (6237000).

Almost surely, 2^81085996 is an apocalyptic number.

It is an amenable number.

81085996 is a deficient number, since it is larger than the sum of its proper divisors (68602004).

81085996 is a wasteful number, since it uses less digits than its factorization.

81085996 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2301 (or 2299 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 46.

The square root of 81085996 is about 9004.7762881706. The cubic root of 81085996 is about 432.8279375458.

The spelling of 81085996 in words is "eighty-one million, eighty-five thousand, nine hundred ninety-six".