1899981 has 24 divisors (see below), whose sum is σ = 2970240. Its totient is φ = 1166400.

The previous prime is 1899949. The next prime is 1899983.

1899981 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1899981 - 2⁵ = 1899949 is a prime.

It is a super-2 number, since 2×1899981² = 7219855600722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1899983) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6876 + ... + 7146.

It is an arithmetic number, because the mean of its divisors is an integer number (123760).

2^1899981 is an apocalyptic number.

It is an amenable number.

1899981 is a deficient number, since it is larger than the sum of its proper divisors (1070259).

1899981 is a wasteful number, since it uses less digits than its factorization.

1899981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 337 (or 334 counting only the distinct ones).

The product of its digits is 46656, while the sum is 45.

The square root of 1899981 is about 1378.3979831674. The cubic root of 1899981 is about 123.8558201075.

It can be divided in two parts, 18 and 99981, that added together give a palindrome (99999).

The spelling of 1899981 in words is "one million, eight hundred ninety-nine thousand, nine hundred eighty-one".