400136401 has 6 divisors (see below), whose sum is σ = 465464850. Its totient is φ = 342974016.

The previous prime is 400136369. The next prime is 400136411. The reversal of 400136401 is 104631004.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 399960001 + 176400 = 19999^2 + 420^2 .

It is not a de Polignac number, because 400136401 - 2⁵ = 400136369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (400136411) 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, 4082976 + ... + 4083073.

It is an arithmetic number, because the mean of its divisors is an integer number (77577475).

Almost surely, 2^400136401 is an apocalyptic number.

It is an amenable number.

400136401 is a deficient number, since it is larger than the sum of its proper divisors (65328449).

400136401 is an equidigital number, since it uses as much as digits as its factorization.

400136401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8166063 (or 8166056 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 400136401 is about 20003.4097343428. The cubic root of 400136401 is about 736.8900411402.

Adding to 400136401 its reverse (104631004), we get a palindrome (504767405).

The spelling of 400136401 in words is "four hundred million, one hundred thirty-six thousand, four hundred one".