1221199963 has 2 divisors, whose sum is σ = 1221199964. Its totient is φ = 1221199962.

The previous prime is 1221199961. The next prime is 1221200011. The reversal of 1221199963 is 3699911221.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1221199963 - 2¹ = 1221199961 is a prime.

Together with 1221199961, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1221199961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610599981 + 610599982.

It is an arithmetic number, because the mean of its divisors is an integer number (610599982).

Almost surely, 2^1221199963 is an apocalyptic number.

1221199963 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221199963 is an equidigital number, since it uses as much as digits as its factorization.

1221199963 is an evil number, because the sum of its binary digits is even.

The product of its digits is 52488, while the sum is 43.

The square root of 1221199963 is about 34945.6715917723. The cubic root of 1221199963 is about 1068.8799421683.

The spelling of 1221199963 in words is "one billion, two hundred twenty-one million, one hundred ninety-nine thousand, nine hundred sixty-three".