172978697098 has 4 divisors (see below), whose sum is σ = 259468045650. Its totient is φ = 86489348548.

The previous prime is 172978697093. The next prime is 172978697131. The reversal of 172978697098 is 890796879271.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 890796879271 = 13 ⋅68522836867.

It can be written as a sum of positive squares in only one way, i.e., 109119890889 + 63858806209 = 330333^2 + 252703^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 172978697098.

It is not an unprimeable number, because it can be changed into a prime (172978697093) 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 as a sum of consecutive naturals, namely, 43244674273 + ... + 43244674276.

Almost surely, 2^172978697098 is an apocalyptic number.

172978697098 is a deficient number, since it is larger than the sum of its proper divisors (86489348552).

172978697098 is an equidigital number, since it uses as much as digits as its factorization.

172978697098 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86489348551.

The product of its (nonzero) digits is 192036096, while the sum is 73.

The spelling of 172978697098 in words is "one hundred seventy-two billion, nine hundred seventy-eight million, six hundred ninety-seven thousand, ninety-eight".