1209129264720 has 640 divisors, whose sum is σ = 4525105374720. Its totient is φ = 294995312640.

The previous prime is 1209129264691. The next prime is 1209129264727. The reversal of 1209129264720 is 274629219021.

1209129264720 is a `hidden beast` number, since 1 + 2 + 0 + 91 + 2 + 92 + 6 + 472 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1209129264727) 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 127 ways as a sum of consecutive naturals, for example, 2311910379 + ... + 2311910901.

It is an arithmetic number, because the mean of its divisors is an integer number (7070477148).

Almost surely, 2^{1209129264720} is an apocalyptic number.

1209129264720 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 1209129264720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2262552687360).

1209129264720 is an abundant number, since it is smaller than the sum of its proper divisors (3315976110000).

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

1209129264720 is a wasteful number, since it uses less digits than its factorization.

1209129264720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1132 (or 1120 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The spelling of 1209129264720 in words is "one trillion, two hundred nine billion, one hundred twenty-nine million, two hundred sixty-four thousand, seven hundred twenty".