6621397 has 4 divisors (see below), whose sum is σ = 6656256. Its totient is φ = 6586540.

The previous prime is 6621379. The next prime is 6621413. The reversal of 6621397 is 7931266.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 6621397 - 2¹⁵ = 6588629 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6621337) 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, 17143 + ... + 17524.

It is an arithmetic number, because the mean of its divisors is an integer number (1664064).

Almost surely, 2^6621397 is an apocalyptic number.

It is an amenable number.

6621397 is a deficient number, since it is larger than the sum of its proper divisors (34859).

6621397 is a wasteful number, since it uses less digits than its factorization.

6621397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34858.

The product of its digits is 13608, while the sum is 34.

The square root of 6621397 is about 2573.2075314673. The cubic root of 6621397 is about 187.7802339959.

The spelling of 6621397 in words is "six million, six hundred twenty-one thousand, three hundred ninety-seven".