165979384381440 has 2448 divisors, whose sum is σ = 702101881091520. Its totient is φ = 36875230248960.

The previous prime is 165979384381403. The next prime is 165979384381441. The reversal of 165979384381440 is 44183483979561.

165979384381440 is a `hidden beast` number, since 1 + 6 + 5 + 9 + 79 + 3 + 84 + 38 + 1 + 440 = 666.

It is a super-2 number, since 2×165979384381440² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165979384381441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 617023733626 + ... + 617023733894.

Almost surely, 2^{165979384381440} is an apocalyptic number.

165979384381440 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 165979384381440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (351050940545760).

165979384381440 is an abundant number, since it is smaller than the sum of its proper divisors (536122496710080).

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

165979384381440 is an frugal number, since it uses more digits than its factorization.

165979384381440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 378 (or 327 counting only the distinct ones).

The product of its (nonzero) digits is 627056640, while the sum is 72.

The spelling of 165979384381440 in words is "one hundred sixty-five trillion, nine hundred seventy-nine billion, three hundred eighty-four million, three hundred eighty-one thousand, four hundred forty".