81878314529 has 8 divisors (see below), whose sum is σ = 89326018080. Its totient is φ = 74431314400.

The previous prime is 81878314489. The next prime is 81878314549. The reversal of 81878314529 is 92541387818.

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-81878314529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81878314549) 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, 84269 + ... + 413349.

It is an arithmetic number, because the mean of its divisors is an integer number (11165752260).

Almost surely, 2^81878314529 is an apocalyptic number.

It is an amenable number.

81878314529 is a deficient number, since it is larger than the sum of its proper divisors (7447703551).

81878314529 is a wasteful number, since it uses less digits than its factorization.

81878314529 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 351711.

The product of its digits is 3870720, while the sum is 56.

The spelling of 81878314529 in words is "eighty-one billion, eight hundred seventy-eight million, three hundred fourteen thousand, five hundred twenty-nine".