1216949272 has 128 divisors (see below), whose sum is σ = 2972505600. Its totient is φ = 456973440.

The previous prime is 1216949257. The next prime is 1216949287. The reversal of 1216949272 is 2729496121.

It is an interprime number because it is at equal distance from previous prime (1216949257) and next prime (1216949287).

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2161263 + ... + 2161825.

It is an arithmetic number, because the mean of its divisors is an integer number (23222700).

Almost surely, 2^1216949272 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1216949272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1486252800).

1216949272 is an abundant number, since it is smaller than the sum of its proper divisors (1755556328).

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

1216949272 is a wasteful number, since it uses less digits than its factorization.

1216949272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 638 (or 612 counting only the distinct ones).

The product of its digits is 108864, while the sum is 43.

The square root of 1216949272 is about 34884.8000137596. The cubic root of 1216949272 is about 1067.6383327471.

The spelling of 1216949272 in words is "one billion, two hundred sixteen million, nine hundred forty-nine thousand, two hundred seventy-two".