81040207 has 8 divisors (see below), whose sum is σ = 86196096. Its totient is φ = 75927552.

The previous prime is 81040189. The next prime is 81040213. The reversal of 81040207 is 70204018.

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 81040207 - 2¹⁵ = 81007439 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81040237) 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, 6898 + ... + 14479.

It is an arithmetic number, because the mean of its divisors is an integer number (10774512).

Almost surely, 2^81040207 is an apocalyptic number.

81040207 is a deficient number, since it is larger than the sum of its proper divisors (5155889).

81040207 is a wasteful number, since it uses less digits than its factorization.

81040207 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21617.

The product of its (nonzero) digits is 448, while the sum is 22.

The square root of 81040207 is about 9002.2334450957. The cubic root of 81040207 is about 432.7464500259.

The spelling of 81040207 in words is "eighty-one million, forty thousand, two hundred seven".