1216336401 has 24 divisors (see below), whose sum is σ = 2040843584. Its totient is φ = 683652960.

The previous prime is 1216336397. The next prime is 1216336427. The reversal of 1216336401 is 1046336121.

1216336401 is a `hidden beast` number, since 1 + 2 + 16 + 3 + 3 + 640 + 1 = 666.

It is not a de Polignac number, because 1216336401 - 2² = 1216336397 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1216336501) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 154411 + ... + 162096.

Almost surely, 2^1216336401 is an apocalyptic number.

It is an amenable number.

1216336401 is a deficient number, since it is larger than the sum of its proper divisors (824507183).

1216336401 is a wasteful number, since it uses less digits than its factorization.

1216336401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316581 (or 316578 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 1216336401 is about 34876.0146949160. The cubic root of 1216336401 is about 1067.4590772759.

The spelling of 1216336401 in words is "one billion, two hundred sixteen million, three hundred thirty-six thousand, four hundred one".