1216105456 has 10 divisors (see below), whose sum is σ = 2356204352. Its totient is φ = 608052720.

The previous prime is 1216105453. The next prime is 1216105483. The reversal of 1216105456 is 6545016121.

It is a super-2 number, since 2×1216105456² = 2957824960225935872, which contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216105453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38003280 + ... + 38003311.

Almost surely, 2^1216105456 is an apocalyptic number.

1216105456 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1216105456 is a deficient number, since it is larger than the sum of its proper divisors (1140098896).

1216105456 is an equidigital number, since it uses as much as digits as its factorization.

1216105456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76006599 (or 76006593 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 31.

The square root of 1216105456 is about 34872.7035946455. The cubic root of 1216105456 is about 1067.3915137465.

The spelling of 1216105456 in words is "one billion, two hundred sixteen million, one hundred five thousand, four hundred fifty-six".