1661120177 has 2 divisors, whose sum is σ = 1661120178. Its totient is φ = 1661120176.

The previous prime is 1661120147. The next prime is 1661120221. The reversal of 1661120177 is 7710211661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 909866896 + 751253281 = 30164^2 + 27409^2 .

It is a cyclic number.

It is not a de Polignac number, because 1661120177 - 2²⁸ = 1392684721 is a prime.

It is a super-2 number, since 2×1661120177² = 5518640484873022658, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1661120137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 830560088 + 830560089.

It is an arithmetic number, because the mean of its divisors is an integer number (830560089).

Almost surely, 2^1661120177 is an apocalyptic number.

It is an amenable number.

1661120177 is a deficient number, since it is larger than the sum of its proper divisors (1).

1661120177 is an equidigital number, since it uses as much as digits as its factorization.

1661120177 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3528, while the sum is 32.

The square root of 1661120177 is about 40756.8420881697. The cubic root of 1661120177 is about 1184.3144216940.

The spelling of 1661120177 in words is "one billion, six hundred sixty-one million, one hundred twenty thousand, one hundred seventy-seven".