1868642005 has 4 divisors (see below), whose sum is σ = 2242370412. Its totient is φ = 1494913600.

The previous prime is 1868642003. The next prime is 1868642053. The reversal of 1868642005 is 5002468681.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 745453809 + 1123188196 = 27303^2 + 33514^2 .

It is not a de Polignac number, because 1868642005 - 2¹ = 1868642003 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1868642003) 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, 186864196 + ... + 186864205.

It is an arithmetic number, because the mean of its divisors is an integer number (560592603).

Almost surely, 2^1868642005 is an apocalyptic number.

It is an amenable number.

1868642005 is a deficient number, since it is larger than the sum of its proper divisors (373728407).

1868642005 is an equidigital number, since it uses as much as digits as its factorization.

1868642005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 373728406.

The product of its (nonzero) digits is 92160, while the sum is 40.

The square root of 1868642005 is about 43227.7920440080. The cubic root of 1868642005 is about 1231.7106664140.

The spelling of 1868642005 in words is "one billion, eight hundred sixty-eight million, six hundred forty-two thousand, five".