7220661 has 16 divisors (see below), whose sum is σ = 11301504. Its totient is φ = 4014144.

The previous prime is 7220621. The next prime is 7220671. The reversal of 7220661 is 1660227.

It is a happy number.

It is not a de Polignac number, because 7220661 - 2⁹ = 7220149 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7220611) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3870 + ... + 5423.

It is an arithmetic number, because the mean of its divisors is an integer number (706344).

Almost surely, 2^7220661 is an apocalyptic number.

It is an amenable number.

7220661 is a deficient number, since it is larger than the sum of its proper divisors (4080843).

7220661 is a wasteful number, since it uses less digits than its factorization.

7220661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9340.

The product of its (nonzero) digits is 1008, while the sum is 24.

The square root of 7220661 is about 2687.1287650576. The cubic root of 7220661 is about 193.2824040113.

Adding to 7220661 its reverse (1660227), we get a palindrome (8880888).

The spelling of 7220661 in words is "seven million, two hundred twenty thousand, six hundred sixty-one".