2172651749 has 2 divisors, whose sum is σ = 2172651750. Its totient is φ = 2172651748.

The previous prime is 2172651721. The next prime is 2172651757. The reversal of 2172651749 is 9471562712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2166250849 + 6400900 = 46543^2 + 2530^2 .

It is a cyclic number.

It is not a de Polignac number, because 2172651749 - 2²⁰ = 2171603173 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2172651779) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1086325874 + 1086325875.

It is an arithmetic number, because the mean of its divisors is an integer number (1086325875).

Almost surely, 2^2172651749 is an apocalyptic number.

It is an amenable number.

2172651749 is a deficient number, since it is larger than the sum of its proper divisors (1).

2172651749 is an equidigital number, since it uses as much as digits as its factorization.

2172651749 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 211680, while the sum is 44.

The square root of 2172651749 is about 46611.7125731291. The cubic root of 2172651749 is about 1295.1797326603.

The spelling of 2172651749 in words is "two billion, one hundred seventy-two million, six hundred fifty-one thousand, seven hundred forty-nine".