1216436243 has 4 divisors (see below), whose sum is σ = 1327021368. Its totient is φ = 1105851120.

The previous prime is 1216436227. The next prime is 1216436341. The reversal of 1216436243 is 3426346121.

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

It is not a de Polignac number, because 1216436243 - 2⁴ = 1216436227 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1216436743) 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, 55292546 + ... + 55292567.

It is an arithmetic number, because the mean of its divisors is an integer number (331755342).

Almost surely, 2^1216436243 is an apocalyptic number.

1216436243 is a deficient number, since it is larger than the sum of its proper divisors (110585125).

1216436243 is a wasteful number, since it uses less digits than its factorization.

1216436243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110585124.

The product of its digits is 20736, while the sum is 32.

The square root of 1216436243 is about 34877.4460504206. The cubic root of 1216436243 is about 1067.4882836515.

The spelling of 1216436243 in words is "one billion, two hundred sixteen million, four hundred thirty-six thousand, two hundred forty-three".