81801070207 has 4 divisors (see below), whose sum is σ = 83344486680. Its totient is φ = 80257653736.

The previous prime is 81801070193. The next prime is 81801070213. The reversal of 81801070207 is 70207010818.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81801070207 - 2¹¹ = 81801068159 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 (81801070217) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 771708157 + ... + 771708262.

It is an arithmetic number, because the mean of its divisors is an integer number (20836121670).

Almost surely, 2^81801070207 is an apocalyptic number.

81801070207 is a deficient number, since it is larger than the sum of its proper divisors (1543416473).

81801070207 is a wasteful number, since it uses less digits than its factorization.

81801070207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1543416472.

The product of its (nonzero) digits is 6272, while the sum is 34.

The spelling of 81801070207 in words is "eighty-one billion, eight hundred one million, seventy thousand, two hundred seven".