1004181779520 has 560 divisors, whose sum is σ = 3668140764288. Its totient is φ = 260623319040.

The previous prime is 1004181779509. The next prime is 1004181779521. The reversal of 1004181779520 is 259771814001.

It is a happy number.

1004181779520 is a `hidden beast` number, since 1 + 0 + 0 + 41 + 8 + 17 + 79 + 520 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (1004181779521) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 346626712 + ... + 346629608.

Almost surely, 2^{1004181779520} is an apocalyptic number.

1004181779520 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 1004181779520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1834070382144).

1004181779520 is an abundant number, since it is smaller than the sum of its proper divisors (2663958984768).

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

1004181779520 is a wasteful number, since it uses less digits than its factorization.

1004181779520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3280 (or 3261 counting only the distinct ones).

The product of its (nonzero) digits is 141120, while the sum is 45.

The spelling of 1004181779520 in words is "one trillion, four billion, one hundred eighty-one million, seven hundred seventy-nine thousand, five hundred twenty".