8400397 has 4 divisors (see below), whose sum is σ = 8894556. Its totient is φ = 7906240.

The previous prime is 8400377. The next prime is 8400409. The reversal of 8400397 is 7930048.

It is a happy number.

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 3511876 + 4888521 = 1874^2 + 2211^2 .

It is a cyclic number.

It is not a de Polignac number, because 8400397 - 2⁷ = 8400269 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8400317) 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, 247054 + ... + 247087.

It is an arithmetic number, because the mean of its divisors is an integer number (2223639).

Almost surely, 2^8400397 is an apocalyptic number.

It is an amenable number.

8400397 is a deficient number, since it is larger than the sum of its proper divisors (494159).

8400397 is a wasteful number, since it uses less digits than its factorization.

8400397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 494158.

The product of its (nonzero) digits is 6048, while the sum is 31.

The square root of 8400397 is about 2898.3438374354. The cubic root of 8400397 is about 203.2824737677.

It can be divided in two parts, 84003 and 97, that added together give a square (84100 = 290²).

The spelling of 8400397 in words is "eight million, four hundred thousand, three hundred ninety-seven".