1209985789320 has 1536 divisors, whose sum is σ = 5173635317760. Its totient is φ = 238049280000.

The previous prime is 1209985789319. The next prime is 1209985789379. The reversal of 1209985789320 is 239875899021.

1209985789320 is a `hidden beast` number, since 1 + 20 + 9 + 9 + 8 + 578 + 9 + 32 + 0 = 666.

It is a super-2 number, since 2×1209985789320² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 9527447097 + ... + 9527447223.

It is an arithmetic number, because the mean of its divisors is an integer number (3368252160).

Almost surely, 2^{1209985789320} is an apocalyptic number.

1209985789320 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 1209985789320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2586817658880).

1209985789320 is an abundant number, since it is smaller than the sum of its proper divisors (3963649528440).

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

1209985789320 is a wasteful number, since it uses less digits than its factorization.

1209985789320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 387 (or 380 counting only the distinct ones).

The product of its (nonzero) digits is 19595520, while the sum is 63.

The spelling of 1209985789320 in words is "one trillion, two hundred nine billion, nine hundred eighty-five million, seven hundred eighty-nine thousand, three hundred twenty".