172199979505 has 8 divisors (see below), whose sum is σ = 206881100712. Its totient is φ = 137599233408.

The previous prime is 172199979499. The next prime is 172199979533. The reversal of 172199979505 is 505979991271.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 43057495009 + 129142484496 = 207503^2 + 359364^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 172199979505 - 2¹³ = 172199971313 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20089062 + ... + 20097631.

It is an arithmetic number, because the mean of its divisors is an integer number (25860137589).

Almost surely, 2^172199979505 is an apocalyptic number.

It is an amenable number.

172199979505 is a deficient number, since it is larger than the sum of its proper divisors (34681121207).

172199979505 is an equidigital number, since it uses as much as digits as its factorization.

172199979505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40187555.

The product of its (nonzero) digits is 16074450, while the sum is 64.

The spelling of 172199979505 in words is "one hundred seventy-two billion, one hundred ninety-nine million, nine hundred seventy-nine thousand, five hundred five".