1216640555430 has 64 divisors (see below), whose sum is σ = 3014296934400. Its totient is φ = 313954248960.

The previous prime is 1216640555387. The next prime is 1216640555437. The reversal of 1216640555430 is 345550466121.

It is a super-2 number, since 2×1216640555430² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216640555437) 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, 29524581 + ... + 29565759.

It is an arithmetic number, because the mean of its divisors is an integer number (47098389600).

Almost surely, 2^{1216640555430} is an apocalyptic number.

1216640555430 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1216640555430 is an abundant number, since it is smaller than the sum of its proper divisors (1797656378970).

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

1216640555430 is a wasteful number, since it uses less digits than its factorization.

1216640555430 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72989.

The product of its (nonzero) digits is 432000, while the sum is 42.

The spelling of 1216640555430 in words is "one trillion, two hundred sixteen billion, six hundred forty million, five hundred fifty-five thousand, four hundred thirty".