1221627663 has 40 divisors (see below), whose sum is σ = 1862356496. Its totient is φ = 797817600.

The previous prime is 1221627647. The next prime is 1221627691. The reversal of 1221627663 is 3667261221.

1221627663 is a `hidden beast` number, since 1 + 2 + 21 + 627 + 6 + 6 + 3 = 666.

It is not a de Polignac number, because 1221627663 - 2⁴ = 1221627647 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 (1221627613) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 2139168 + ... + 2139738.

Almost surely, 2^1221627663 is an apocalyptic number.

1221627663 is a deficient number, since it is larger than the sum of its proper divisors (640728833).

1221627663 is an equidigital number, since it uses as much as digits as its factorization.

1221627663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1077 (or 1068 counting only the distinct ones).

The product of its digits is 36288, while the sum is 36.

The square root of 1221627663 is about 34951.7905549916. The cubic root of 1221627663 is about 1069.0047119590.

Adding to 1221627663 its reverse (3667261221), we get a palindrome (4888888884).

The spelling of 1221627663 in words is "one billion, two hundred twenty-one million, six hundred twenty-seven thousand, six hundred sixty-three".