40728181 has 8 divisors (see below), whose sum is σ = 44881760. Its totient is φ = 36720432.

The previous prime is 40728169. The next prime is 40728187. The reversal of 40728181 is 18182704.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40728181 is a prime.

It is a super-2 number, since 2×40728181² = 3317569455137522, 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 (40728187) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35871 + ... + 36988.

It is an arithmetic number, because the mean of its divisors is an integer number (5610220).

Almost surely, 2^40728181 is an apocalyptic number.

It is an amenable number.

40728181 is a deficient number, since it is larger than the sum of its proper divisors (4153579).

40728181 is a wasteful number, since it uses less digits than its factorization.

40728181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72915.

The product of its (nonzero) digits is 3584, while the sum is 31.

The square root of 40728181 is about 6381.8634426004. The cubic root of 40728181 is about 344.0580086283.

The spelling of 40728181 in words is "forty million, seven hundred twenty-eight thousand, one hundred eighty-one".