1900161 has 6 divisors (see below), whose sum is σ = 2744690. Its totient is φ = 1266768.

The previous prime is 1900159. The next prime is 1900169. The reversal of 1900161 is 1610091.

It can be written as a sum of positive squares in only one way, i.e., 1703025 + 197136 = 1305^2 + 444^2 .

It is not a de Polignac number, because 1900161 - 2¹ = 1900159 is a prime.

It is a super-3 number, since 3×1900161³ = 20582231333261619843, which contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1900169) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 105556 + ... + 105573.

2^1900161 is an apocalyptic number.

It is an amenable number.

1900161 is a deficient number, since it is larger than the sum of its proper divisors (844529).

1900161 is a wasteful number, since it uses less digits than its factorization.

1900161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 211135 (or 211132 counting only the distinct ones).

The product of its (nonzero) digits is 54, while the sum is 18.

The square root of 1900161 is about 1378.4632748100. The cubic root of 1900161 is about 123.8597312596.

The spelling of 1900161 in words is "one million, nine hundred thousand, one hundred sixty-one".