161757049 has 2 divisors, whose sum is σ = 161757050. Its totient is φ = 161757048.

The previous prime is 161757047. The next prime is 161757053. The reversal of 161757049 is 940757161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 157628025 + 4129024 = 12555^2 + 2032^2 .

It is a cyclic number.

It is not a de Polignac number, because 161757049 - 2¹ = 161757047 is a prime.

Together with 161757047, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (161757047) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80878524 + 80878525.

It is an arithmetic number, because the mean of its divisors is an integer number (80878525).

Almost surely, 2^161757049 is an apocalyptic number.

It is an amenable number.

161757049 is a deficient number, since it is larger than the sum of its proper divisors (1).

161757049 is an equidigital number, since it uses as much as digits as its factorization.

161757049 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 52920, while the sum is 40.

The square root of 161757049 is about 12718.3744637434. The cubic root of 161757049 is about 544.8635283803.

The spelling of 161757049 in words is "one hundred sixty-one million, seven hundred fifty-seven thousand, forty-nine".