1216614401 has 4 divisors (see below), whose sum is σ = 1288179972. Its totient is φ = 1145048832.

The previous prime is 1216614383. The next prime is 1216614433. The reversal of 1216614401 is 1044166121.

It is a Cunningham number, because it is equal to 34880²+1.

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

It can be written as a sum of positive squares in 2 ways, for example, as 947162176 + 269452225 = 30776^2 + 16415^2 .

It is a cyclic number.

It is not a de Polignac number, because 1216614401 - 2¹⁸ = 1216352257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1216614461) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35782760 + ... + 35782793.

It is an arithmetic number, because the mean of its divisors is an integer number (322044993).

Almost surely, 2^1216614401 is an apocalyptic number.

It is an amenable number.

1216614401 is a deficient number, since it is larger than the sum of its proper divisors (71565571).

1216614401 is an equidigital number, since it uses as much as digits as its factorization.

1216614401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71565570.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 1216614401 is about 34880.0000143349. Note that the first 4 decimals coincide. The cubic root of 1216614401 is about 1067.5403955192.

The spelling of 1216614401 in words is "one billion, two hundred sixteen million, six hundred fourteen thousand, four hundred one".