400644155 has 16 divisors (see below), whose sum is σ = 502579200. Its totient is φ = 306240480.

The previous prime is 400644109. The next prime is 400644247. The reversal of 400644155 is 551446004.

It is not a de Polignac number, because 400644155 - 2¹⁴ = 400627771 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, 4115 + ... + 28604.

It is an arithmetic number, because the mean of its divisors is an integer number (31411200).

Almost surely, 2^400644155 is an apocalyptic number.

400644155 is a deficient number, since it is larger than the sum of its proper divisors (101935045).

400644155 is a wasteful number, since it uses less digits than its factorization.

400644155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32834.

The product of its (nonzero) digits is 9600, while the sum is 29.

The square root of 400644155 is about 20016.0973968454. The cubic root of 400644155 is about 737.2016021589.

The spelling of 400644155 in words is "four hundred million, six hundred forty-four thousand, one hundred fifty-five".