172779657245 has 16 divisors (see below), whose sum is σ = 223354940592. Its totient is φ = 127550868480.

The previous prime is 172779657241. The next prime is 172779657269. The reversal of 172779657245 is 542756977271.

It can be written as a sum of positive squares in 8 ways, for example, as 22311695641 + 150467961604 = 149371^2 + 387902^2 .

It is not a de Polignac number, because 172779657245 - 2² = 172779657241 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172779657241) 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 in 15 ways as a sum of consecutive naturals, for example, 211052 + ... + 624581.

It is an arithmetic number, because the mean of its divisors is an integer number (13959683787).

Almost surely, 2^172779657245 is an apocalyptic number.

It is an amenable number.

172779657245 is a deficient number, since it is larger than the sum of its proper divisors (50575283347).

172779657245 is a wasteful number, since it uses less digits than its factorization.

172779657245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 838832.

The product of its digits is 51861600, while the sum is 62.

The spelling of 172779657245 in words is "one hundred seventy-two billion, seven hundred seventy-nine million, six hundred fifty-seven thousand, two hundred forty-five".