6401405 has 4 divisors (see below), whose sum is σ = 7681692. Its totient is φ = 5121120.

The previous prime is 6401399. The next prime is 6401411. The reversal of 6401405 is 5041046.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (6401399) and next prime (6401411).

It can be written as a sum of positive squares in 2 ways, for example, as 3541924 + 2859481 = 1882^2 + 1691^2 .

It is not a de Polignac number, because 6401405 - 2⁴ = 6401389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 640136 + ... + 640145.

It is an arithmetic number, because the mean of its divisors is an integer number (1920423).

Almost surely, 2^6401405 is an apocalyptic number.

It is an amenable number.

6401405 is a deficient number, since it is larger than the sum of its proper divisors (1280287).

6401405 is a wasteful number, since it uses less digits than its factorization.

6401405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1280286.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 6401405 is about 2530.0998004031. The cubic root of 6401405 is about 185.6771386677.

The spelling of 6401405 in words is "six million, four hundred one thousand, four hundred five".