81072907 has 8 divisors (see below), whose sum is σ = 84720384. Its totient is φ = 77435688.

The previous prime is 81072877. The next prime is 81072911. The reversal of 81072907 is 70927018.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81072907 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81072917) 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, 16788 + ... + 21070.

It is an arithmetic number, because the mean of its divisors is an integer number (10590048).

Almost surely, 2^81072907 is an apocalyptic number.

81072907 is a deficient number, since it is larger than the sum of its proper divisors (3647477).

81072907 is a wasteful number, since it uses less digits than its factorization.

81072907 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5129.

The product of its (nonzero) digits is 7056, while the sum is 34.

The square root of 81072907 is about 9004.0494778738. The cubic root of 81072907 is about 432.8046470887.

The spelling of 81072907 in words is "eighty-one million, seventy-two thousand, nine hundred seven".