1221083137 has 4 divisors (see below), whose sum is σ = 1221190740. Its totient is φ = 1220975536.

The previous prime is 1221083131. The next prime is 1221083159. The reversal of 1221083137 is 7313801221.

It is a Cunningham number, because it is equal to 34944²+1.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 7313801221 = 83 ⋅88118087.

It can be written as a sum of positive squares in 2 ways, for example, as 735277456 + 485805681 = 27116^2 + 22041^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221083137 - 2⁷ = 1221083009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221083131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34462 + ... + 60247.

It is an arithmetic number, because the mean of its divisors is an integer number (305297685).

Almost surely, 2^1221083137 is an apocalyptic number.

It is an amenable number.

1221083137 is a deficient number, since it is larger than the sum of its proper divisors (107603).

1221083137 is an equidigital number, since it uses as much as digits as its factorization.

1221083137 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107602.

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 1221083137 is about 34944.0000143086. Note that the first 4 decimals coincide. The cubic root of 1221083137 is about 1068.8458563090.

Adding to 1221083137 its reverse (7313801221), we get a palindrome (8534884358).

The spelling of 1221083137 in words is "one billion, two hundred twenty-one million, eighty-three thousand, one hundred thirty-seven".