81156415907 has 8 divisors (see below), whose sum is σ = 94322227200. Its totient is φ = 68383614024.

The previous prime is 81156415903. The next prime is 81156415937. The reversal of 81156415907 is 70951465118.

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 81156415907 - 2² = 81156415903 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81156415903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 98251907 + ... + 98252732.

It is an arithmetic number, because the mean of its divisors is an integer number (11790278400).

Almost surely, 2^81156415907 is an apocalyptic number.

81156415907 is a deficient number, since it is larger than the sum of its proper divisors (13165811293).

81156415907 is a wasteful number, since it uses less digits than its factorization.

81156415907 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196504705.

The product of its (nonzero) digits is 302400, while the sum is 47.

The spelling of 81156415907 in words is "eighty-one billion, one hundred fifty-six million, four hundred fifteen thousand, nine hundred seven".