1216643434 has 4 divisors (see below), whose sum is σ = 1824965154. Its totient is φ = 608321716.

The previous prime is 1216643431. The next prime is 1216643479. The reversal of 1216643434 is 4343466121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 4343466121 = 241 ⋅18022681.

It can be written as a sum of positive squares in only one way, i.e., 902822209 + 313821225 = 30047^2 + 17715^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1216643434.

It is not an unprimeable number, because it can be changed into a prime (1216643431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 304160857 + ... + 304160860.

Almost surely, 2^1216643434 is an apocalyptic number.

1216643434 is a deficient number, since it is larger than the sum of its proper divisors (608321720).

1216643434 is an equidigital number, since it uses as much as digits as its factorization.

1216643434 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 608321719.

The product of its digits is 41472, while the sum is 34.

The square root of 1216643434 is about 34880.4161959114. The cubic root of 1216643434 is about 1067.5488872960.

The spelling of 1216643434 in words is "one billion, two hundred sixteen million, six hundred forty-three thousand, four hundred thirty-four".