81196254040 has 64 divisors (see below), whose sum is σ = 204160914720. Its totient is φ = 28805760000.

The previous prime is 81196254017. The next prime is 81196254047. The reversal of 81196254040 is 4045269118.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 81196253984 and 81196254002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81196254047) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2232411 + ... + 2268490.

Almost surely, 2^81196254040 is an apocalyptic number.

It is an amenable number.

81196254040 is an abundant number, since it is smaller than the sum of its proper divisors (122964660680).

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

81196254040 is a wasteful number, since it uses less digits than its factorization.

81196254040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4500964 (or 4500960 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 40.

The spelling of 81196254040 in words is "eighty-one billion, one hundred ninety-six million, two hundred fifty-four thousand, forty".