400138600 has 24 divisors (see below), whose sum is σ = 930322710. Its totient is φ = 160055360.

The previous prime is 400138597. The next prime is 400138603. The reversal of 400138600 is 6831004.

It is an interprime number because it is at equal distance from previous prime (400138597) and next prime (400138603).

It can be written as a sum of positive squares in 3 ways, for example, as 306320004 + 93818596 = 17502^2 + 9686^2 .

It is a super-2 number, since 2×400138600² = 320221798419920000, which contains 22 as substring.

400138600 is a modest number, since divided by 138600 gives 400 as remainder.

It is not an unprimeable number, because it can be changed into a prime (400138603) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1000147 + ... + 1000546.

Almost surely, 2^400138600 is an apocalyptic number.

400138600 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

400138600 is an abundant number, since it is smaller than the sum of its proper divisors (530184110).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

400138600 is a wasteful number, since it uses less digits than its factorization.

400138600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2000709 (or 2000700 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 400138600 is about 20003.4646998964. The cubic root of 400138600 is about 736.8913910284.

Adding to 400138600 its reverse (6831004), we get a palindrome (406969604).

The spelling of 400138600 in words is "four hundred million, one hundred thirty-eight thousand, six hundred".