81970219968 has 168 divisors, whose sum is σ = 271695653712. Its totient is φ = 21618487296.

The previous prime is 81970219967. The next prime is 81970219979. The reversal of 81970219968 is 86991207918.

It is a tau number, because it is divible by the number of its divisors (168).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81970219963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 212805 + ... + 457412.

It is an arithmetic number, because the mean of its divisors is an integer number (1617236034).

Almost surely, 2^81970219968 is an apocalyptic number.

It is an amenable number.

81970219968 is an abundant number, since it is smaller than the sum of its proper divisors (189725433744).

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

81970219968 is a wasteful number, since it uses less digits than its factorization.

81970219968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 670259 (or 670242 counting only the distinct ones).

The product of its (nonzero) digits is 3919104, while the sum is 60.

The spelling of 81970219968 in words is "eighty-one billion, nine hundred seventy million, two hundred nineteen thousand, nine hundred sixty-eight".