400155555 has 32 divisors (see below), whose sum is σ = 664421184. Its totient is φ = 205479936.

The previous prime is 400155551. The next prime is 400155577. The reversal of 400155555 is 555551004.

It is not a de Polignac number, because 400155555 - 2² = 400155551 is a prime.

It is not an unprimeable number, because it can be changed into a prime (400155551) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 50119 + ... + 57551.

It is an arithmetic number, because the mean of its divisors is an integer number (20763162).

Almost surely, 2^400155555 is an apocalyptic number.

400155555 is a deficient number, since it is larger than the sum of its proper divisors (264265629).

400155555 is a wasteful number, since it uses less digits than its factorization.

400155555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7575.

The product of its (nonzero) digits is 12500, while the sum is 30.

The square root of 400155555 is about 20003.8884969898. Note that the first 3 decimals coincide. The cubic root of 400155555 is about 736.9017989363.

The spelling of 400155555 in words is "four hundred million, one hundred fifty-five thousand, five hundred fifty-five".