7818401 has 4 divisors (see below), whose sum is σ = 7965972. Its totient is φ = 7670832.

The previous prime is 7818397. The next prime is 7818451. The reversal of 7818401 is 1048187.

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

It can be written as a sum of positive squares in 2 ways, for example, as 4752400 + 3066001 = 2180^2 + 1751^2 .

It is a cyclic number.

It is not a de Polignac number, because 7818401 - 2² = 7818397 is a prime.

It is a super-2 number, since 2×7818401² = 122254788393602, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7818451) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 73706 + ... + 73811.

It is an arithmetic number, because the mean of its divisors is an integer number (1991493).

Almost surely, 2^7818401 is an apocalyptic number.

It is an amenable number.

7818401 is a deficient number, since it is larger than the sum of its proper divisors (147571).

7818401 is a wasteful number, since it uses less digits than its factorization.

7818401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147570.

The product of its (nonzero) digits is 1792, while the sum is 29.

The square root of 7818401 is about 2796.1403755892. The cubic root of 7818401 is about 198.4750776088.

The spelling of 7818401 in words is "seven million, eight hundred eighteen thousand, four hundred one".