7122821 has 8 divisors (see below), whose sum is σ = 7343424. Its totient is φ = 6904800.

The previous prime is 7122809. The next prime is 7122859. The reversal of 7122821 is 1282217.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 7122821 - 2⁶ = 7122757 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 (7122121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5945 + ... + 7041.

It is an arithmetic number, because the mean of its divisors is an integer number (917928).

Almost surely, 2^7122821 is an apocalyptic number.

It is an amenable number.

7122821 is a deficient number, since it is larger than the sum of its proper divisors (220603).

7122821 is a wasteful number, since it uses less digits than its factorization.

7122821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1291.

The product of its digits is 448, while the sum is 23.

The square root of 7122821 is about 2668.8613676997. The cubic root of 7122821 is about 192.4054384610.

The spelling of 7122821 in words is "seven million, one hundred twenty-two thousand, eight hundred twenty-one".