1216690623389 has 2 divisors, whose sum is σ = 1216690623390. Its totient is φ = 1216690623388.

The previous prime is 1216690623371. The next prime is 1216690623397. The reversal of 1216690623389 is 9833260966121.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1179087596164 + 37603027225 = 1085858^2 + 193915^2 .

It is a cyclic number.

It is not a de Polignac number, because 1216690623389 - 2¹⁶ = 1216690557853 is a prime.

It is a super-3 number, since 3×1216690623389³ (a number of 37 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1216690620389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 608345311694 + 608345311695.

It is an arithmetic number, because the mean of its divisors is an integer number (608345311695).

Almost surely, 2^{1216690623389} is an apocalyptic number.

It is an amenable number.

1216690623389 is a deficient number, since it is larger than the sum of its proper divisors (1).

1216690623389 is an equidigital number, since it uses as much as digits as its factorization.

1216690623389 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5038848, while the sum is 56.

The spelling of 1216690623389 in words is "one trillion, two hundred sixteen billion, six hundred ninety million, six hundred twenty-three thousand, three hundred eighty-nine".