40401 has 9 divisors (see below), whose sum is σ = 59241. Its totient is φ = 26532.

The previous prime is 40387. The next prime is 40423. The reversal of 40401 is 10404.

40401 = T₂₀₀ + T₂₀₁.

The square root of 40401 is 201.

It is a perfect power (a square), and thus also a powerful number.

It is a tau number, because it is divible by the number of its divisors (9).

It is a de Polignac number, because none of the positive numbers 2^k-40401 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (40471) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 570 + ... + 636.

2⁴⁰⁴⁰¹ is an apocalyptic number.

40401 is the 201-st square number.

40401 is the 101-st centered octagonal number.

It is an amenable number.

40401 is a deficient number, since it is larger than the sum of its proper divisors (18840).

40401 is an equidigital number, since it uses as much as digits as its factorization.

40401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140 (or 70 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

The cubic root of 40401 is about 34.3134225418.

Multiplying 40401 by its product of nonzero digits (16), we get a square (646416 = 804²).

Adding to 40401 its reverse (10404), we get a palindrome (50805).

Multiplying 40401 by its reverse (10404), we get a square (420332004 = 20502²).

It can be divided in two parts, 40 and 401, that added together give a square (441 = 21²).

The spelling of 40401 in words is "forty thousand, four hundred one", and thus it is an iban number.