2172505897 has 2 divisors, whose sum is σ = 2172505898. Its totient is φ = 2172505896.

The previous prime is 2172505873. The next prime is 2172505901. The reversal of 2172505897 is 7985052712.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1507691241 + 664814656 = 38829^2 + 25784^2 .

It is a cyclic number.

It is not a de Polignac number, because 2172505897 - 2¹¹ = 2172503849 is a prime.

It is not a weakly prime, because it can be changed into another prime (2172505597) 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, 1086252948 + 1086252949.

It is an arithmetic number, because the mean of its divisors is an integer number (1086252949).

Almost surely, 2^2172505897 is an apocalyptic number.

It is an amenable number.

2172505897 is a deficient number, since it is larger than the sum of its proper divisors (1).

2172505897 is an equidigital number, since it uses as much as digits as its factorization.

2172505897 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 352800, while the sum is 46.

The square root of 2172505897 is about 46610.1480044850. The cubic root of 2172505897 is about 1295.1507498314.

The spelling of 2172505897 in words is "two billion, one hundred seventy-two million, five hundred five thousand, eight hundred ninety-seven".