3981240605 has 4 divisors (see below), whose sum is σ = 4777488732. Its totient is φ = 3184992480.

The previous prime is 3981240559. The next prime is 3981240623. The reversal of 3981240605 is 5060421893.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5060421893 = 46141 ⋅109673.

It can be written as a sum of positive squares in 2 ways, for example, as 1705855204 + 2275385401 = 41302^2 + 47701^2 .

It is not a de Polignac number, because 3981240605 - 2¹² = 3981236509 is a prime.

It is a super-3 number, since 3×3981240605³ (a number of 30 digits) contains 333 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 398124056 + ... + 398124065.

It is an arithmetic number, because the mean of its divisors is an integer number (1194372183).

Almost surely, 2^3981240605 is an apocalyptic number.

It is an amenable number.

3981240605 is a deficient number, since it is larger than the sum of its proper divisors (796248127).

3981240605 is an equidigital number, since it uses as much as digits as its factorization.

3981240605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 796248126.

The product of its (nonzero) digits is 51840, while the sum is 38.

The square root of 3981240605 is about 63097.0728718853. The cubic root of 3981240605 is about 1584.9156055069.

The spelling of 3981240605 in words is "three billion, nine hundred eighty-one million, two hundred forty thousand, six hundred five".