5819981 has 4 divisors (see below), whose sum is σ = 6020700. Its totient is φ = 5619264.

The previous prime is 5819969. The next prime is 5819987. The reversal of 5819981 is 1899185.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1899185 = 5 ⋅379837.

It can be written as a sum of positive squares in 2 ways, for example, as 2788900 + 3031081 = 1670^2 + 1741^2 .

It is a cyclic number.

It is not a de Polignac number, because 5819981 - 2¹⁴ = 5803597 is a prime.

It is a super-2 number, since 2×5819981² = 67744357680722, 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 (5819987) 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, 100316 + ... + 100373.

It is an arithmetic number, because the mean of its divisors is an integer number (1505175).

Almost surely, 2^5819981 is an apocalyptic number.

It is an amenable number.

5819981 is a deficient number, since it is larger than the sum of its proper divisors (200719).

5819981 is a wasteful number, since it uses less digits than its factorization.

5819981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200718.

The product of its digits is 25920, while the sum is 41.

The square root of 5819981 is about 2412.4636784831. The cubic root of 5819981 is about 179.8762626954.

The spelling of 5819981 in words is "five million, eight hundred nineteen thousand, nine hundred eighty-one".