7840001 has 4 divisors (see below), whose sum is σ = 8443092. Its totient is φ = 7236912.

The previous prime is 7839961. The next prime is 7840013. The reversal of 7840001 is 1000487.

It is a happy number.

It is a Cunningham number, because it is equal to 2800²+1.

7840001 is an esthetic number in base 7, because in such base its adjacent digits differ by 1.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1000487 = 311 ⋅3217.

It can be written as a sum of positive squares in 2 ways, for example, as 1157776 + 6682225 = 1076^2 + 2585^2 .

It is a cyclic number.

It is not a de Polignac number, because 7840001 - 2¹⁴ = 7823617 is a prime.

It is a super-2 number, since 2×7840001² = 122931231360002, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (7840031) 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, 301526 + ... + 301551.

It is an arithmetic number, because the mean of its divisors is an integer number (2110773).

Almost surely, 2^7840001 is an apocalyptic number.

It is an amenable number.

7840001 is a deficient number, since it is larger than the sum of its proper divisors (603091).

7840001 is a wasteful number, since it uses less digits than its factorization.

7840001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 603090.

The product of its (nonzero) digits is 224, while the sum is 20.

The square root of 7840001 is about 2800.0001785714. Note that the first 3 decimals coincide. The cubic root of 7840001 is about 198.6576861222.

Adding to 7840001 its reverse (1000487), we get a palindrome (8840488).

The spelling of 7840001 in words is "seven million, eight hundred forty thousand, one".