2157773549 has 2 divisors, whose sum is σ = 2157773550. Its totient is φ = 2157773548.

The previous prime is 2157773539. The next prime is 2157773587. The reversal of 2157773549 is 9453777512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1203396100 + 954377449 = 34690^2 + 30893^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2157773549 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2157773497 and 2157773506.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2157773509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1078886774 + 1078886775.

It is an arithmetic number, because the mean of its divisors is an integer number (1078886775).

Almost surely, 2^2157773549 is an apocalyptic number.

It is an amenable number.

2157773549 is a deficient number, since it is larger than the sum of its proper divisors (1).

2157773549 is an equidigital number, since it uses as much as digits as its factorization.

2157773549 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1852200, while the sum is 50.

The square root of 2157773549 is about 46451.8411798714. The cubic root of 2157773549 is about 1292.2165184341.

The spelling of 2157773549 in words is "two billion, one hundred fifty-seven million, seven hundred seventy-three thousand, five hundred forty-nine".