1800240161 has 2 divisors, whose sum is σ = 1800240162. Its totient is φ = 1800240160.

The previous prime is 1800240157. The next prime is 1800240181. The reversal of 1800240161 is 1610420081.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1591611025 + 208629136 = 39895^2 + 14444^2 .

It is a cyclic number.

It is not a de Polignac number, because 1800240161 - 2² = 1800240157 is a prime.

It is not a weakly prime, because it can be changed into another prime (1800240181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 900120080 + 900120081.

It is an arithmetic number, because the mean of its divisors is an integer number (900120081).

Almost surely, 2^1800240161 is an apocalyptic number.

It is an amenable number.

1800240161 is a deficient number, since it is larger than the sum of its proper divisors (1).

1800240161 is an equidigital number, since it uses as much as digits as its factorization.

1800240161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 384, while the sum is 23.

The square root of 1800240161 is about 42429.2371013197. The cubic root of 1800240161 is about 1216.4944969945.

The spelling of 1800240161 in words is "one billion, eight hundred million, two hundred forty thousand, one hundred sixty-one".