3999997181 has 4 divisors (see below), whose sum is σ = 4085103552. Its totient is φ = 3914890812.

The previous prime is 3999997163. The next prime is 3999997237. The reversal of 3999997181 is 1817999993.

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.

It is a cyclic number.

It is not a de Polignac number, because 3999997181 - 2⁶ = 3999997117 is a prime.

It is a super-2 number, since 2×3999997181² = 31999954896015893522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3999997121) 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, 42553115 + ... + 42553208.

It is an arithmetic number, because the mean of its divisors is an integer number (1021275888).

Almost surely, 2^3999997181 is an apocalyptic number.

It is an amenable number.

3999997181 is a deficient number, since it is larger than the sum of its proper divisors (85106371).

3999997181 is an equidigital number, since it uses as much as digits as its factorization.

3999997181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85106370.

The product of its digits is 9920232, while the sum is 65.

The square root of 3999997181 is about 63245.5309172119. The cubic root of 3999997181 is about 1587.4006790611.

The spelling of 3999997181 in words is "three billion, nine hundred ninety-nine million, nine hundred ninety-seven thousand, one hundred eighty-one".