217478055554992 has 20 divisors (see below), whose sum is σ = 421384770940720. Its totient is φ = 108733598538048.

The previous prime is 217478055554989. The next prime is 217478055555017. The reversal of 217478055554992 is 299455550874712.

It is a super-2 number, since 2×217478055554992² (a number of 29 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 338996988 + ... + 339637915.

It is an arithmetic number, because the mean of its divisors is an integer number (21069238547036).

Almost surely, 2^{217478055554992} is an apocalyptic number.

It is an amenable number.

217478055554992 is a deficient number, since it is larger than the sum of its proper divisors (203906715385728).

217478055554992 is a wasteful number, since it uses less digits than its factorization.

217478055554992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 678654940 (or 678654934 counting only the distinct ones).

The product of its (nonzero) digits is 1270080000, while the sum is 73.

The spelling of 217478055554992 in words is "two hundred seventeen trillion, four hundred seventy-eight billion, fifty-five million, five hundred fifty-four thousand, nine hundred ninety-two".