1216390615802 has 4 divisors (see below), whose sum is σ = 1824585923706. Its totient is φ = 608195307900.

The previous prime is 1216390615747. The next prime is 1216390615807. The reversal of 1216390615802 is 2085160936121.

It is a happy number.

It is a Cunningham number, because it is equal to 1102901²+1.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1216390615801 + 1 = 1102901^2 + 1^2 .

It is a super-3 number, since 3×1216390615802³ (a number of 37 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (1216390615807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 304097653949 + ... + 304097653952.

Almost surely, 2^{1216390615802} is an apocalyptic number.

1216390615802 is a deficient number, since it is larger than the sum of its proper divisors (608195307904).

1216390615802 is an equidigital number, since it uses as much as digits as its factorization.

1216390615802 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 608195307903.

The product of its (nonzero) digits is 155520, while the sum is 44.

The spelling of 1216390615802 in words is "one trillion, two hundred sixteen billion, three hundred ninety million, six hundred fifteen thousand, eight hundred two".