1216398901900 has 576 divisors, whose sum is σ = 3450163175424. Its totient is φ = 362041344000.

The previous prime is 1216398901847. The next prime is 1216398901901. The reversal of 1216398901900 is 91098936121.

It is a super-2 number, since 2×1216398901900² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1216398901901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 1245034212 + ... + 1245035188.

It is an arithmetic number, because the mean of its divisors is an integer number (5989866624).

Almost surely, 2^{1216398901900} is an apocalyptic number.

1216398901900 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 1216398901900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1725081587712).

1216398901900 is an abundant number, since it is smaller than the sum of its proper divisors (2233764273524).

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

1216398901900 is a wasteful number, since it uses less digits than its factorization.

1216398901900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1170 (or 1163 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 49.

The spelling of 1216398901900 in words is "one trillion, two hundred sixteen billion, three hundred ninety-eight million, nine hundred one thousand, nine hundred".