39994181 has 4 divisors (see below), whose sum is σ = 40041600. Its totient is φ = 39946764.

The previous prime is 39994159. The next prime is 39994193. The reversal of 39994181 is 18149993.

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: 18149993 = 59 ⋅307627.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-39994181 is a prime.

It is a super-2 number, since 2×39994181² = 3199069027721522, 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 (39994121) 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, 22421 + ... + 24138.

It is an arithmetic number, because the mean of its divisors is an integer number (10010400).

Almost surely, 2^39994181 is an apocalyptic number.

It is an amenable number.

39994181 is a deficient number, since it is larger than the sum of its proper divisors (47419).

39994181 is an equidigital number, since it uses as much as digits as its factorization.

39994181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47418.

The product of its digits is 69984, while the sum is 44.

The square root of 39994181 is about 6324.0952712621. The cubic root of 39994181 is about 341.9786046144.

The spelling of 39994181 in words is "thirty-nine million, nine hundred ninety-four thousand, one hundred eighty-one".