1217998080 has 288 divisors, whose sum is σ = 4656395520. Its totient is φ = 299704320.

The previous prime is 1217998049. The next prime is 1217998081. The reversal of 1217998080 is 808997121.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1217998081) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 447925 + ... + 450635.

It is an arithmetic number, because the mean of its divisors is an integer number (16168040).

Almost surely, 2^1217998080 is an apocalyptic number.

1217998080 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 1217998080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2328197760).

1217998080 is an abundant number, since it is smaller than the sum of its proper divisors (3438397440).

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

1217998080 is a wasteful number, since it uses less digits than its factorization.

1217998080 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2754 (or 2734 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 45.

The square root of 1217998080 is about 34899.8292259432. The cubic root of 1217998080 is about 1067.9449536078.

The spelling of 1217998080 in words is "one billion, two hundred seventeen million, nine hundred ninety-eight thousand, eighty".