1800101 has 4 divisors (see below), whose sum is σ = 1802892. Its totient is φ = 1797312.

The previous prime is 1800091. The next prime is 1800103. The reversal of 1800101 is 1010081.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 297025 + 1503076 = 545^2 + 1226^2 .

It is a cyclic number.

It is not a de Polignac number, because 1800101 - 2⁶ = 1800037 is a prime.

It is a super-2 number, since 2×1800101² = 6480727220402, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1800103) 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, 125 + ... + 1901.

It is an arithmetic number, because the mean of its divisors is an integer number (450723).

2^1800101 is an apocalyptic number.

It is an amenable number.

1800101 is a deficient number, since it is larger than the sum of its proper divisors (2791).

1800101 is a wasteful number, since it uses less digits than its factorization.

1800101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2790.

The product of its (nonzero) digits is 8, while the sum is 11.

The square root of 1800101 is about 1341.6784264495. The cubic root of 1800101 is about 121.6463150630.

Adding to 1800101 its reverse (1010081), we get a palindrome (2810182).

The spelling of 1800101 in words is "one million, eight hundred thousand, one hundred one".