81867097200 has 240 divisors, whose sum is σ = 317342188800. Its totient is φ = 17611714560.

The previous prime is 81867097199. The next prime is 81867097211. The reversal of 81867097200 is 279076818.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 81867097200.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 143850 + ... + 429449.

It is an arithmetic number, because the mean of its divisors is an integer number (1322259120).

Almost surely, 2^81867097200 is an apocalyptic number.

81867097200 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81867097200 is an abundant number, since it is smaller than the sum of its proper divisors (235475091600).

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

81867097200 is a wasteful number, since it uses less digits than its factorization.

81867097200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 573344 (or 573333 counting only the distinct ones).

The product of its (nonzero) digits is 338688, while the sum is 48.

The spelling of 81867097200 in words is "eighty-one billion, eight hundred sixty-seven million, ninety-seven thousand, two hundred".