165266438400 has 2592 divisors, whose sum is σ = 797108981760. Its totient is φ = 32965263360.

The previous prime is 165266438377. The next prime is 165266438431. The reversal of 165266438400 is 4834662561.

165266438400 is a `hidden beast` number, since 1 + 6 + 5 + 266 + 4 + 384 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (2592).

It is a super-2 number, since 2×165266438400² (a number of 23 digits) contains 22 as substring.

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

It is a congruent number.

It is an unprimeable number.

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 287 ways as a sum of consecutive naturals, for example, 3516307177 + ... + 3516307223.

Almost surely, 2^165266438400 is an apocalyptic number.

165266438400 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 165266438400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (398554490880).

165266438400 is an abundant number, since it is smaller than the sum of its proper divisors (631842543360).

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

165266438400 is a wasteful number, since it uses less digits than its factorization.

165266438400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131 (or 100 counting only the distinct ones).

The product of its (nonzero) digits is 829440, while the sum is 45.

The spelling of 165266438400 in words is "one hundred sixty-five billion, two hundred sixty-six million, four hundred thirty-eight thousand, four hundred".