81651198703 has 8 divisors (see below), whose sum is σ = 81960032000. Its totient is φ = 81342937368.

The previous prime is 81651198631. The next prime is 81651198721. The reversal of 81651198703 is 30789115618.

It is a happy number.

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 81651198703 - 2²⁵ = 81617644271 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 (81651198743) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 144148 + ... + 429046.

It is an arithmetic number, because the mean of its divisors is an integer number (10245004000).

Almost surely, 2^81651198703 is an apocalyptic number.

81651198703 is a deficient number, since it is larger than the sum of its proper divisors (308833297).

81651198703 is a wasteful number, since it uses less digits than its factorization.

81651198703 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 285981.

The product of its (nonzero) digits is 362880, while the sum is 49.

The spelling of 81651198703 in words is "eighty-one billion, six hundred fifty-one million, one hundred ninety-eight thousand, seven hundred three".