400004145 has 24 divisors (see below), whose sum is σ = 704711592. Its totient is φ = 209836800.

The previous prime is 400004123. The next prime is 400004161. The reversal of 400004145 is 541400004.

It can be written as a sum of positive squares in 4 ways, for example, as 4511376 + 395492769 = 2124^2 + 19887^2 .

It is not a de Polignac number, because 400004145 - 2¹² = 400000049 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 70116 + ... + 75605.

It is an arithmetic number, because the mean of its divisors is an integer number (29362983).

Almost surely, 2^400004145 is an apocalyptic number.

400004145 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

It is an amenable number.

400004145 is a deficient number, since it is larger than the sum of its proper divisors (304707447).

400004145 is a wasteful number, since it uses less digits than its factorization.

400004145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145793 (or 145790 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 400004145 is about 20000.1036247315. The cubic root of 400004145 is about 736.8088447710.

Adding to 400004145 its reverse (541400004), we get a palindrome (941404149).

The spelling of 400004145 in words is "four hundred million, four thousand, one hundred forty-five".