1217968740 has 72 divisors (see below), whose sum is σ = 3911838840. Its totient is φ = 305685504.

The previous prime is 1217968733. The next prime is 1217968747. The reversal of 1217968740 is 478697121.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1217968733) and next prime (1217968747).

It can be written as a sum of positive squares in 4 ways, for example, as 567106596 + 650862144 = 23814^2 + 25512^2 .

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

It is not an unprimeable number, because it can be changed into a prime (1217968747) 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 23 ways as a sum of consecutive naturals, for example, 195955 + ... + 202074.

It is an arithmetic number, because the mean of its divisors is an integer number (54331095).

Almost surely, 2^1217968740 is an apocalyptic number.

1217968740 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1217968740 is an abundant number, since it is smaller than the sum of its proper divisors (2693870100).

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

1217968740 is a wasteful number, since it uses less digits than its factorization.

1217968740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 398061 (or 398056 counting only the distinct ones).

The product of its (nonzero) digits is 169344, while the sum is 45.

The square root of 1217968740 is about 34899.4088775154. The cubic root of 1217968740 is about 1067.9363784009.

The spelling of 1217968740 in words is "one billion, two hundred seventeen million, nine hundred sixty-eight thousand, seven hundred forty".