81197455919454 has 64 divisors (see below), whose sum is σ = 206221673018880. Its totient is φ = 23198608025280.

The previous prime is 81197455919389. The next prime is 81197455919491. The reversal of 81197455919454 is 45491955479118.

81197455919454 is a `hidden beast` number, since 8 + 1 + 1 + 9 + 7 + 4 + 559 + 19 + 4 + 54 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10199017 + ... + 16322219.

It is an arithmetic number, because the mean of its divisors is an integer number (3222213640920).

Almost surely, 2^{81197455919454} is an apocalyptic number.

81197455919454 is an abundant number, since it is smaller than the sum of its proper divisors (125024217099426).

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

81197455919454 is a wasteful number, since it uses less digits than its factorization.

81197455919454 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6158302 (or 6158296 counting only the distinct ones).

The product of its digits is 326592000, while the sum is 72.

The spelling of 81197455919454 in words is "eighty-one trillion, one hundred ninety-seven billion, four hundred fifty-five million, nine hundred nineteen thousand, four hundred fifty-four".