71997222578 has 6 divisors (see below), whose sum is σ = 107996403069. Its totient is φ = 35998421556.

The previous prime is 71997222571. The next prime is 71997222593. The reversal of 71997222578 is 87522279917.

It can be written as a sum of positive squares in 2 ways, for example, as 71806313089 + 190909489 = 267967^2 + 13817^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=189733.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71997222571) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 284600 + ... + 474332.

Almost surely, 2^71997222578 is an apocalyptic number.

71997222578 is a deficient number, since it is larger than the sum of its proper divisors (35999180491).

71997222578 is an frugal number, since it uses more digits than its factorization.

71997222578 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 379468 (or 189735 counting only the distinct ones).

The product of its digits is 8890560, while the sum is 59.

The spelling of 71997222578 in words is "seventy-one billion, nine hundred ninety-seven million, two hundred twenty-two thousand, five hundred seventy-eight".