1217688780 has 192 divisors, whose sum is σ = 4331916288. Its totient is φ = 248202240.

The previous prime is 1217688779. The next prime is 1217688781. The reversal of 1217688780 is 878867121.

It is an interprime number because it is at equal distance from previous prime (1217688779) and next prime (1217688781).

It is not an unprimeable number, because it can be changed into a prime (1217688781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 242374 + ... + 247346.

It is an arithmetic number, because the mean of its divisors is an integer number (22562064).

Almost surely, 2^1217688780 is an apocalyptic number.

1217688780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1217688780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2165958144).

1217688780 is an abundant number, since it is smaller than the sum of its proper divisors (3114227508).

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

1217688780 is a wasteful number, since it uses less digits than its factorization.

1217688780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5056 (or 5054 counting only the distinct ones).

The product of its (nonzero) digits is 301056, while the sum is 48.

The square root of 1217688780 is about 34895.3976908130. The cubic root of 1217688780 is about 1067.8545475161.

The spelling of 1217688780 in words is "one billion, two hundred seventeen million, six hundred eighty-eight thousand, seven hundred eighty".