400128755 has 16 divisors (see below), whose sum is σ = 517601280. Its totient is φ = 295187328.

The previous prime is 400128731. The next prime is 400128793. The reversal of 400128755 is 557821004.

It is a cyclic number.

It is not a de Polignac number, because 400128755 - 2⁶ = 400128691 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 80729 + ... + 85541.

It is an arithmetic number, because the mean of its divisors is an integer number (32350080).

Almost surely, 2^400128755 is an apocalyptic number.

400128755 is a deficient number, since it is larger than the sum of its proper divisors (117472525).

400128755 is a wasteful number, since it uses less digits than its factorization.

400128755 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6110.

The product of its (nonzero) digits is 11200, while the sum is 32.

The square root of 400128755 is about 20003.2186160128. The cubic root of 400128755 is about 736.8853474931.

Adding to 400128755 its reverse (557821004), we get a palindrome (957949759).

The spelling of 400128755 in words is "four hundred million, one hundred twenty-eight thousand, seven hundred fifty-five".