2190161 has 4 divisors (see below), whose sum is σ = 2319012. Its totient is φ = 2061312.

The previous prime is 2190157. The next prime is 2190169. The reversal of 2190161 is 1610912.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1345600 + 844561 = 1160^2 + 919^2 .

It is a cyclic number.

It is not a de Polignac number, because 2190161 - 2² = 2190157 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2190169) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64400 + ... + 64433.

It is an arithmetic number, because the mean of its divisors is an integer number (579753).

2^2190161 is an apocalyptic number.

It is an amenable number.

2190161 is a deficient number, since it is larger than the sum of its proper divisors (128851).

2190161 is a wasteful number, since it uses less digits than its factorization.

2190161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128850.

The product of its (nonzero) digits is 108, while the sum is 20.

The square root of 2190161 is about 1479.9192545541. The cubic root of 2190161 is about 129.8649682716.

The spelling of 2190161 in words is "two million, one hundred ninety thousand, one hundred sixty-one".