1216571139840 has 576 divisors, whose sum is σ = 4656748723200. Its totient is φ = 264794406912.

The previous prime is 1216571139803. The next prime is 1216571139841. The reversal of 1216571139840 is 489311756121.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 1216571139840.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216571139841) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 56894271 + ... + 56915649.

It is an arithmetic number, because the mean of its divisors is an integer number (8084633200).

It is a 1-persistent number, because it is pandigital, but 2⋅1216571139840 = 2433142279680 is not.

Almost surely, 2^{1216571139840} is an apocalyptic number.

1216571139840 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 1216571139840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2328374361600).

1216571139840 is an abundant number, since it is smaller than the sum of its proper divisors (3440177583360).

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

1216571139840 is a wasteful number, since it uses less digits than its factorization.

1216571139840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21512 (or 21498 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 48.

The spelling of 1216571139840 in words is "one trillion, two hundred sixteen billion, five hundred seventy-one million, one hundred thirty-nine thousand, eight hundred forty".