1861801 has 4 divisors (see below), whose sum is σ = 1866112. Its totient is φ = 1857492.

The previous prime is 1861787. The next prime is 1861807. The reversal of 1861801 is 1081681.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1861801 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1861807) 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, 1425 + ... + 2398.

It is an arithmetic number, because the mean of its divisors is an integer number (466528).

2^1861801 is an apocalyptic number.

It is an amenable number.

1861801 is a deficient number, since it is larger than the sum of its proper divisors (4311).

1861801 is an equidigital number, since it uses as much as digits as its factorization.

1861801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4310.

The product of its (nonzero) digits is 384, while the sum is 25.

The square root of 1861801 is about 1364.4782885777. The cubic root of 1861801 is about 123.0205751378.

It can be divided in two parts, 1861 and 801, that added together give a palindrome (2662).

The spelling of 1861801 in words is "one million, eight hundred sixty-one thousand, eight hundred one".