1216145204 has 6 divisors (see below), whose sum is σ = 2128254114. Its totient is φ = 608072600.

The previous prime is 1216145191. The next prime is 1216145209. The reversal of 1216145204 is 4025416121.

It can be written as a sum of positive squares in only one way, i.e., 1029768100 + 186377104 = 32090^2 + 13652^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216145209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 152018147 + ... + 152018154.

It is an arithmetic number, because the mean of its divisors is an integer number (354709019).

Almost surely, 2^1216145204 is an apocalyptic number.

It is an amenable number.

1216145204 is a deficient number, since it is larger than the sum of its proper divisors (912108910).

1216145204 is a wasteful number, since it uses less digits than its factorization.

1216145204 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 304036305 (or 304036303 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 1216145204 is about 34873.2734913142. The cubic root of 1216145204 is about 1067.4031427313.

The spelling of 1216145204 in words is "one billion, two hundred sixteen million, one hundred forty-five thousand, two hundred four".