1216329456 has 20 divisors (see below), whose sum is σ = 3142184552. Its totient is φ = 405443136.

The previous prime is 1216329407. The next prime is 1216329461. The reversal of 1216329456 is 6549236121.

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 3 ways as a sum of consecutive naturals, for example, 12670051 + ... + 12670146.

Almost surely, 2^1216329456 is an apocalyptic number.

1216329456 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1216329456 is an abundant number, since it is smaller than the sum of its proper divisors (1925855096).

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

1216329456 is a wasteful number, since it uses less digits than its factorization.

1216329456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25340208 (or 25340202 counting only the distinct ones).

The product of its digits is 77760, while the sum is 39.

The square root of 1216329456 is about 34875.9151277784. The cubic root of 1216329456 is about 1067.4570456237.

The spelling of 1216329456 in words is "one billion, two hundred sixteen million, three hundred twenty-nine thousand, four hundred fifty-six".