981280809661644 has 192 divisors, whose sum is σ = 2714393429637120. Its totient is φ = 305489419822080.

The previous prime is 981280809661643. The next prime is 981280809661667. The reversal of 981280809661644 is 446166908082189.

981280809661644 is a `hidden beast` number, since 98 + 1 + 280 + 80 + 96 + 61 + 6 + 44 = 666.

It is a Smith number, since the sum of its digits (72) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (981280809661643) 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, 6476298574 + ... + 6476450090.

It is an arithmetic number, because the mean of its divisors is an integer number (14137465779360).

Almost surely, 2^{981280809661644} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 981280809661644, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1357196714818560).

981280809661644 is an abundant number, since it is smaller than the sum of its proper divisors (1733112619975476).

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

981280809661644 is a wasteful number, since it uses less digits than its factorization.

981280809661644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178605 (or 178597 counting only the distinct ones).

The product of its (nonzero) digits is 286654464, while the sum is 72.

The spelling of 981280809661644 in words is "nine hundred eighty-one trillion, two hundred eighty billion, eight hundred nine million, six hundred sixty-one thousand, six hundred forty-four".