1861883081 has 4 divisors (see below), whose sum is σ = 1864992000. Its totient is φ = 1858774164.

The previous prime is 1861883077. The next prime is 1861883137. The reversal of 1861883081 is 1803881681.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1803881681 = 7 ⋅257697383.

It is a cyclic number.

It is not a de Polignac number, because 1861883081 - 2² = 1861883077 is a prime.

It is a super-2 number, since 2×1861883081² = 6933217214628105122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1861883011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1553561 + ... + 1554758.

It is an arithmetic number, because the mean of its divisors is an integer number (466248000).

Almost surely, 2^1861883081 is an apocalyptic number.

It is an amenable number.

1861883081 is a deficient number, since it is larger than the sum of its proper divisors (3108919).

1861883081 is an equidigital number, since it uses as much as digits as its factorization.

1861883081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3108918.

The product of its (nonzero) digits is 73728, while the sum is 44.

The square root of 1861883081 is about 43149.5432304909. The cubic root of 1861883081 is about 1230.2238297576.

The spelling of 1861883081 in words is "one billion, eight hundred sixty-one million, eight hundred eighty-three thousand, eighty-one".