7220662121 has 4 divisors (see below), whose sum is σ = 7469650500. Its totient is φ = 6971673744.

The previous prime is 7220662117. The next prime is 7220662133. The reversal of 7220662121 is 1212660227.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1212660227 = 7919 ⋅153133.

It can be written as a sum of positive squares in 2 ways, for example, as 5487105625 + 1733556496 = 74075^2 + 41636^2 .

It is a cyclic number.

It is not a de Polignac number, because 7220662121 - 2² = 7220662117 is a prime.

It is a super-2 number, since 2×7220662121² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (29), and also a Moran number because the ratio is a prime number: 248988349 = 7220662121 / (7 + 2 + 2 + 0 + 6 + 6 + 2 + 1 + 2 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7220662181) 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, 124494146 + ... + 124494203.

It is an arithmetic number, because the mean of its divisors is an integer number (1867412625).

Almost surely, 2^7220662121 is an apocalyptic number.

It is an amenable number.

7220662121 is a deficient number, since it is larger than the sum of its proper divisors (248988379).

7220662121 is a wasteful number, since it uses less digits than its factorization.

7220662121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248988378.

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 7220662121 is about 84974.4792334734. The cubic root of 7220662121 is about 1932.8241401363.

The spelling of 7220662121 in words is "seven billion, two hundred twenty million, six hundred sixty-two thousand, one hundred twenty-one".