6997865221 has 4 divisors (see below), whose sum is σ = 6998145772. Its totient is φ = 6997584672.

The previous prime is 6997865219. The next prime is 6997865233. The reversal of 6997865221 is 1225687996.

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 1306822500 + 5691042721 = 36150^2 + 75439^2 .

It is a cyclic number.

It is not a de Polignac number, because 6997865221 - 2¹ = 6997865219 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 (6997865521) 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, 98766 + ... + 154111.

It is an arithmetic number, because the mean of its divisors is an integer number (1749536443).

Almost surely, 2^6997865221 is an apocalyptic number.

It is an amenable number.

6997865221 is a deficient number, since it is larger than the sum of its proper divisors (280551).

6997865221 is a wasteful number, since it uses less digits than its factorization.

6997865221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 280550.

The product of its digits is 3265920, while the sum is 55.

The square root of 6997865221 is about 83653.2439359048. The cubic root of 6997865221 is about 1912.7367017953.

The spelling of 6997865221 in words is "six billion, nine hundred ninety-seven million, eight hundred sixty-five thousand, two hundred twenty-one".