1251221163 has 8 divisors (see below), whose sum is σ = 1722110976. Its totient is φ = 807239400.

The previous prime is 1251221129. The next prime is 1251221239. The reversal of 1251221163 is 3611221521.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1251221163 - 2¹⁸ = 1250959019 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1251221113) 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, 6726903 + ... + 6727088.

It is an arithmetic number, because the mean of its divisors is an integer number (215263872).

Almost surely, 2^1251221163 is an apocalyptic number.

1251221163 is a deficient number, since it is larger than the sum of its proper divisors (470889813).

1251221163 is a wasteful number, since it uses less digits than its factorization.

1251221163 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13454025.

The product of its digits is 720, while the sum is 24.

The square root of 1251221163 is about 35372.6046962900. The cubic root of 1251221163 is about 1077.5680196364.

Adding to 1251221163 its reverse (3611221521), we get a palindrome (4862442684).

The spelling of 1251221163 in words is "one billion, two hundred fifty-one million, two hundred twenty-one thousand, one hundred sixty-three".