1216603501 has 2 divisors, whose sum is σ = 1216603502. Its totient is φ = 1216603500.

The previous prime is 1216603481. The next prime is 1216603523. The reversal of 1216603501 is 1053066121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 927263401 + 289340100 = 30451^2 + 17010^2 .

It is an emirp because it is prime and its reverse (1053066121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1216603501 - 2²³ = 1208214893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1216603571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 608301750 + 608301751.

It is an arithmetic number, because the mean of its divisors is an integer number (608301751).

Almost surely, 2^1216603501 is an apocalyptic number.

It is an amenable number.

1216603501 is a deficient number, since it is larger than the sum of its proper divisors (1).

1216603501 is an equidigital number, since it uses as much as digits as its factorization.

1216603501 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 1216603501 is about 34879.8437639850. The cubic root of 1216603501 is about 1067.5372073754.

Adding to 1216603501 its reverse (1053066121), we get a palindrome (2269669622).

The spelling of 1216603501 in words is "one billion, two hundred sixteen million, six hundred three thousand, five hundred one".