1216454780 has 24 divisors (see below), whose sum is σ = 2557988160. Its totient is φ = 485928000.

The previous prime is 1216454777. The next prime is 1216454783. The reversal of 1216454780 is 874546121.

It is an interprime number because it is at equal distance from previous prime (1216454777) and next prime (1216454783).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216454783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25475 + ... + 55514.

It is an arithmetic number, because the mean of its divisors is an integer number (106582840).

Almost surely, 2^1216454780 is an apocalyptic number.

1216454780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1216454780 is an abundant number, since it is smaller than the sum of its proper divisors (1341533380).

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

1216454780 is a wasteful number, since it uses less digits than its factorization.

1216454780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81749 (or 81747 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 38.

The square root of 1216454780 is about 34877.7117942104. The cubic root of 1216454780 is about 1067.4937060290.

The spelling of 1216454780 in words is "one billion, two hundred sixteen million, four hundred fifty-four thousand, seven hundred eighty".