172978497858 has 8 divisors (see below), whose sum is σ = 345956995728. Its totient is φ = 57659499284.

The previous prime is 172978497847. The next prime is 172978497859. The reversal of 172978497858 is 858794879271.

It is a sphenic number, since it is the product of 3 distinct primes.

172978497858 is an admirable number.

It is a super-2 number, since 2×172978497858² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 172978497858.

It is not an unprimeable number, because it can be changed into a prime (172978497859) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14414874816 + ... + 14414874827.

It is an arithmetic number, because the mean of its divisors is an integer number (43244624466).

Almost surely, 2^172978497858 is an apocalyptic number.

172978497858 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

172978497858 is a wasteful number, since it uses less digits than its factorization.

172978497858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28829749648.

The product of its digits is 568995840, while the sum is 75.

The spelling of 172978497858 in words is "one hundred seventy-two billion, nine hundred seventy-eight million, four hundred ninety-seven thousand, eight hundred fifty-eight".