1216802149 has 4 divisors (see below), whose sum is σ = 1288378764. Its totient is φ = 1145225536.

The previous prime is 1216802137. The next prime is 1216802219. The reversal of 1216802149 is 9412086121.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1085241249 + 131560900 = 32943^2 + 11470^2 .

It is not a de Polignac number, because 1216802149 - 2⁷ = 1216802021 is a prime.

It is a super-2 number, since 2×1216802149² = 2961214939622036402, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216842149) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35788282 + ... + 35788315.

It is an arithmetic number, because the mean of its divisors is an integer number (322094691).

Almost surely, 2^1216802149 is an apocalyptic number.

It is an amenable number.

1216802149 is a deficient number, since it is larger than the sum of its proper divisors (71576615).

1216802149 is an equidigital number, since it uses as much as digits as its factorization.

1216802149 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71576614.

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 1216802149 is about 34882.6912522529. The cubic root of 1216802149 is about 1067.5953069918.

The spelling of 1216802149 in words is "one billion, two hundred sixteen million, eight hundred two thousand, one hundred forty-nine".