1216631033 has 4 divisors (see below), whose sum is σ = 1216707408. Its totient is φ = 1216554660.

The previous prime is 1216631029. The next prime is 1216631063. The reversal of 1216631033 is 3301366121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 3301366121 = 1499 ⋅2202379.

It is a cyclic number.

It is not a de Polignac number, because 1216631033 - 2² = 1216631029 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1216630993 and 1216631011.

It is not an unprimeable number, because it can be changed into a prime (1216631063) 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, 4223 + ... + 49508.

It is an arithmetic number, because the mean of its divisors is an integer number (304176852).

Almost surely, 2^1216631033 is an apocalyptic number.

It is an amenable number.

1216631033 is a deficient number, since it is larger than the sum of its proper divisors (76375).

1216631033 is an equidigital number, since it uses as much as digits as its factorization.

1216631033 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76374.

The product of its (nonzero) digits is 1944, while the sum is 26.

The square root of 1216631033 is about 34880.2384309511. The cubic root of 1216631033 is about 1067.5452601805.

Adding to 1216631033 its reverse (3301366121), we get a palindrome (4517997154).

The spelling of 1216631033 in words is "one billion, two hundred sixteen million, six hundred thirty-one thousand, thirty-three".