7968821 has 6 divisors (see below), whose sum is σ = 9269910. Its totient is φ = 6830376.

The previous prime is 7968817. The next prime is 7968853. The reversal of 7968821 is 1288697.

It can be written as a sum of positive squares in only one way, i.e., 7761796 + 207025 = 2786^2 + 455^2 .

It is not a de Polignac number, because 7968821 - 2² = 7968817 is a prime.

It is an Ulam 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 (7968811) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 81266 + ... + 81363.

It is an arithmetic number, because the mean of its divisors is an integer number (1544985).

Almost surely, 2^7968821 is an apocalyptic number.

It is an amenable number.

7968821 is a deficient number, since it is larger than the sum of its proper divisors (1301089).

7968821 is a wasteful number, since it uses less digits than its factorization.

7968821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162643 (or 162636 counting only the distinct ones).

The product of its digits is 48384, while the sum is 41.

The square root of 7968821 is about 2822.9100233624. The cubic root of 7968821 is about 199.7398367221.

The spelling of 7968821 in words is "seven million, nine hundred sixty-eight thousand, eight hundred twenty-one".