1216949838 has 16 divisors (see below), whose sum is σ = 2621122896. Its totient is φ = 374446080.

The previous prime is 1216949831. The next prime is 1216949893. The reversal of 1216949838 is 8389496121.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216949831) 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 in 7 ways as a sum of consecutive naturals, for example, 7800883 + ... + 7801038.

It is an arithmetic number, because the mean of its divisors is an integer number (163820181).

Almost surely, 2^1216949838 is an apocalyptic number.

1216949838 is an abundant number, since it is smaller than the sum of its proper divisors (1404173058).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1216949838 is a wasteful number, since it uses less digits than its factorization.

1216949838 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15601939.

The product of its digits is 746496, while the sum is 51.

The square root of 1216949838 is about 34884.8081261744. The cubic root of 1216949838 is about 1067.6384982657.

The spelling of 1216949838 in words is "one billion, two hundred sixteen million, nine hundred forty-nine thousand, eight hundred thirty-eight".