1216869228 has 36 divisors (see below), whose sum is σ = 3077216688. Its totient is φ = 405459360.

The previous prime is 1216869223. The next prime is 1216869233. The reversal of 1216869228 is 8229686121.

It is an interprime number because it is at equal distance from previous prime (1216869223) and next prime (1216869233).

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (1216869221) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 111913 + ... + 122303.

Almost surely, 2^1216869228 is an apocalyptic number.

1216869228 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

1216869228 is an abundant number, since it is smaller than the sum of its proper divisors (1860347460).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1216869228 is a wasteful number, since it uses less digits than its factorization.

1216869228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13654 (or 13649 counting only the distinct ones).

The product of its digits is 165888, while the sum is 45.

The square root of 1216869228 is about 34883.6527330496. The cubic root of 1216869228 is about 1067.6149245086.

The spelling of 1216869228 in words is "one billion, two hundred sixteen million, eight hundred sixty-nine thousand, two hundred twenty-eight".