1216326345 has 64 divisors (see below), whose sum is σ = 2164022784. Its totient is φ = 579502080.

The previous prime is 1216326341. The next prime is 1216326383. The reversal of 1216326345 is 5436236121.

It is not a de Polignac number, because 1216326345 - 2² = 1216326341 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1216326341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1897225 + ... + 1897865.

It is an arithmetic number, because the mean of its divisors is an integer number (33812856).

Almost surely, 2^1216326345 is an apocalyptic number.

1216326345 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1216326345 is a deficient number, since it is larger than the sum of its proper divisors (947696439).

1216326345 is a wasteful number, since it uses less digits than its factorization.

1216326345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 962.

The product of its digits is 25920, while the sum is 33.

The square root of 1216326345 is about 34875.8705267697. The cubic root of 1216326345 is about 1067.4561355464.

The spelling of 1216326345 in words is "one billion, two hundred sixteen million, three hundred twenty-six thousand, three hundred forty-five".