400640164 has 6 divisors (see below), whose sum is σ = 701120294. Its totient is φ = 200320080.

The previous prime is 400640161. The next prime is 400640171. The reversal of 400640164 is 461046004.

It can be written as a sum of positive squares in only one way, i.e., 396806400 + 3833764 = 19920^2 + 1958^2 .

It is not an unprimeable number, because it can be changed into a prime (400640161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50080017 + ... + 50080024.

Almost surely, 2^400640164 is an apocalyptic number.

It is an amenable number.

400640164 is a deficient number, since it is larger than the sum of its proper divisors (300480130).

400640164 is a wasteful number, since it uses less digits than its factorization.

400640164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100160045 (or 100160043 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 400640164 is about 20015.9977018384. The cubic root of 400640164 is about 737.1991542831.

Adding to 400640164 its reverse (461046004), we get a palindrome (861686168).

The spelling of 400640164 in words is "four hundred million, six hundred forty thousand, one hundred sixty-four".