81978103152 has 120 divisors (see below), whose sum is σ = 263454447360. Its totient is φ = 23534375040.

The previous prime is 81978103099. The next prime is 81978103153. The reversal of 81978103152 is 25130187918.

It is a junction number, because it is equal to n+sod(n) for n = 81978103098 and 81978103107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81978103153) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1331848 + ... + 1392039.

It is an arithmetic number, because the mean of its divisors is an integer number (2195453728).

Almost surely, 2^81978103152 is an apocalyptic number.

It is an amenable number.

81978103152 is an abundant number, since it is smaller than the sum of its proper divisors (181476344208).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81978103152 is a wasteful number, since it uses less digits than its factorization.

81978103152 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2723931 (or 2723922 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 45.

The spelling of 81978103152 in words is "eighty-one billion, nine hundred seventy-eight million, one hundred three thousand, one hundred fifty-two".