400666055 has 4 divisors (see below), whose sum is σ = 480799272. Its totient is φ = 320532840.

The previous prime is 400666051. The next prime is 400666087. The reversal of 400666055 is 550666004.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 400666055 - 2² = 400666051 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400666051) 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, 40066601 + ... + 40066610.

It is an arithmetic number, because the mean of its divisors is an integer number (120199818).

Almost surely, 2^400666055 is an apocalyptic number.

400666055 is a deficient number, since it is larger than the sum of its proper divisors (80133217).

400666055 is an equidigital number, since it uses as much as digits as its factorization.

400666055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80133216.

The product of its (nonzero) digits is 21600, while the sum is 32.

The square root of 400666055 is about 20016.6444490579. The cubic root of 400666055 is about 737.2150342122.

The spelling of 400666055 in words is "four hundred million, six hundred sixty-six thousand, fifty-five".