40128730 has 8 divisors (see below), whose sum is σ = 72231732. Its totient is φ = 16051488.

The previous prime is 40128719. The next prime is 40128731. The reversal of 40128730 is 3782104.

It can be written as a sum of positive squares in 2 ways, for example, as 39576681 + 552049 = 6291^2 + 743^2 .

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

It is a super-2 number, since 2×40128730² = 3220629942825800, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 40128695 and 40128704.

It is not an unprimeable number, because it can be changed into a prime (40128731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2006427 + ... + 2006446.

Almost surely, 2^40128730 is an apocalyptic number.

40128730 is a deficient number, since it is larger than the sum of its proper divisors (32103002).

40128730 is a wasteful number, since it uses less digits than its factorization.

40128730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4012880.

The product of its (nonzero) digits is 1344, while the sum is 25.

The square root of 40128730 is about 6334.7241455331. The cubic root of 40128730 is about 342.3616718113.

The spelling of 40128730 in words is "forty million, one hundred twenty-eight thousand, seven hundred thirty".