164647840 has 72 divisors (see below), whose sum is σ = 452509092. Its totient is φ = 56448000.

The previous prime is 164647801. The next prime is 164647859. The reversal of 164647840 is 48746461.

It can be written as a sum of positive squares in 2 ways, for example, as 156650256 + 7997584 = 12516^2 + 2828^2 .

It is a super-2 number, since 2×164647840² = 54217822433331200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 164647793 and 164647802.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2661 + ... + 18340.

Almost surely, 2^164647840 is an apocalyptic number.

164647840 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 164647840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (226254546).

164647840 is an abundant number, since it is smaller than the sum of its proper divisors (287861252).

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

164647840 is a wasteful number, since it uses less digits than its factorization.

164647840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21030 (or 21015 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 40.

The square root of 164647840 is about 12831.5174472858. The cubic root of 164647840 is about 548.0901693314.

The spelling of 164647840 in words is "one hundred sixty-four million, six hundred forty-seven thousand, eight hundred forty".