1216901537 has 2 divisors, whose sum is σ = 1216901538. Its totient is φ = 1216901536.

The previous prime is 1216901507. The next prime is 1216901551. The reversal of 1216901537 is 7351096121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1209926656 + 6974881 = 34784^2 + 2641^2 .

It is an emirp because it is prime and its reverse (7351096121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1216901537 - 2¹² = 1216897441 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1216901497 and 1216901506.

It is not a weakly prime, because it can be changed into another prime (1216901507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 608450768 + 608450769.

It is an arithmetic number, because the mean of its divisors is an integer number (608450769).

Almost surely, 2^1216901537 is an apocalyptic number.

It is an amenable number.

1216901537 is a deficient number, since it is larger than the sum of its proper divisors (1).

1216901537 is an equidigital number, since it uses as much as digits as its factorization.

1216901537 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11340, while the sum is 35.

The square root of 1216901537 is about 34884.1158265478. The cubic root of 1216901537 is about 1067.6243731451.

Adding to 1216901537 its reverse (7351096121), we get a palindrome (8567997658).

The spelling of 1216901537 in words is "one billion, two hundred sixteen million, nine hundred one thousand, five hundred thirty-seven".