1213049881 has 2 divisors, whose sum is σ = 1213049882. Its totient is φ = 1213049880.

The previous prime is 1213049879. The next prime is 1213049899. The reversal of 1213049881 is 1889403121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1177587856 + 35462025 = 34316^2 + 5955^2 .

It is a cyclic number.

It is not a de Polignac number, because 1213049881 - 2¹ = 1213049879 is a prime.

It is a super-2 number, since 2×1213049881² = 2942980027588228322, which contains 22 as substring.

Together with 1213049879, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 1213049881.

It is not a weakly prime, because it can be changed into another prime (1213049801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606524940 + 606524941.

It is an arithmetic number, because the mean of its divisors is an integer number (606524941).

Almost surely, 2^1213049881 is an apocalyptic number.

It is an amenable number.

1213049881 is a deficient number, since it is larger than the sum of its proper divisors (1).

1213049881 is an equidigital number, since it uses as much as digits as its factorization.

1213049881 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13824, while the sum is 37.

The square root of 1213049881 is about 34828.8656289578. The cubic root of 1213049881 is about 1066.4967913828.

The spelling of 1213049881 in words is "one billion, two hundred thirteen million, forty-nine thousand, eight hundred eighty-one".