1220012640 has 288 divisors, whose sum is σ = 5191070976. Its totient is φ = 253486080.

The previous prime is 1220012611. The next prime is 1220012653. The reversal of 1220012640 is 462100221.

1220012640 is a `hidden beast` number, since 1 + 2 + 20 + 0 + 1 + 2 + 640 = 666.

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

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 105379 + ... + 116381.

It is an arithmetic number, because the mean of its divisors is an integer number (18024552).

Almost surely, 2^1220012640 is an apocalyptic number.

1220012640 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 1220012640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2595535488).

1220012640 is an abundant number, since it is smaller than the sum of its proper divisors (3971058336).

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

1220012640 is a wasteful number, since it uses less digits than its factorization.

1220012640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11042 (or 11031 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 1220012640 is about 34928.6793337509. The cubic root of 1220012640 is about 1068.5334203590.

Adding to 1220012640 its reverse (462100221), we get a palindrome (1682112861).

The spelling of 1220012640 in words is "one billion, two hundred twenty million, twelve thousand, six hundred forty".