7221663 has 8 divisors (see below), whose sum is σ = 10698800. Its totient is φ = 4814424.

The previous prime is 7221661. The next prime is 7221689. The reversal of 7221663 is 3661227.

It is a happy number.

It is not a de Polignac number, because 7221663 - 2¹ = 7221661 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 267469 = 7221663 / (7 + 2 + 2 + 1 + 6 + 6 + 3).

It is a Duffinian number.

7221663 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7221661) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 133708 + ... + 133761.

It is an arithmetic number, because the mean of its divisors is an integer number (1337350).

Almost surely, 2^7221663 is an apocalyptic number.

7221663 is a deficient number, since it is larger than the sum of its proper divisors (3477137).

7221663 is a wasteful number, since it uses less digits than its factorization.

7221663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 267478 (or 267472 counting only the distinct ones).

The product of its digits is 3024, while the sum is 27.

The square root of 7221663 is about 2687.3152029488. The cubic root of 7221663 is about 193.2913440983.

The spelling of 7221663 in words is "seven million, two hundred twenty-one thousand, six hundred sixty-three".