400158728 has 16 divisors (see below), whose sum is σ = 750613500. Its totient is φ = 199995136.

The previous prime is 400158727. The next prime is 400158749. The reversal of 400158728 is 827851004.

It can be written as a sum of positive squares in 2 ways, for example, as 366263044 + 33895684 = 19138^2 + 5822^2 .

It is not an unprimeable number, because it can be changed into a prime (400158727) 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, 12668 + ... + 30996.

Almost surely, 2^400158728 is an apocalyptic number.

It is an amenable number.

400158728 is a deficient number, since it is larger than the sum of its proper divisors (350454772).

400158728 is a wasteful number, since it uses less digits than its factorization.

400158728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21064 (or 21060 counting only the distinct ones).

The product of its (nonzero) digits is 17920, while the sum is 35.

The square root of 400158728 is about 20003.9678064128. The cubic root of 400158728 is about 736.9037466649.

The spelling of 400158728 in words is "four hundred million, one hundred fifty-eight thousand, seven hundred twenty-eight".