164821520 has 40 divisors (see below), whose sum is σ = 390450456. Its totient is φ = 64683008.

The previous prime is 164821507. The next prime is 164821543. The reversal of 164821520 is 25128461.

It can be written as a sum of positive squares in 4 ways, for example, as 82882816 + 81938704 = 9104^2 + 9052^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×164821520² = 54332266910220800, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15197 + ... + 23676.

Almost surely, 2^164821520 is an apocalyptic number.

164821520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

164821520 is an abundant number, since it is smaller than the sum of its proper divisors (225628936).

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

164821520 is a wasteful number, since it uses less digits than its factorization.

164821520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38939 (or 38933 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 29.

The square root of 164821520 is about 12838.2833743457. The cubic root of 164821520 is about 548.2828206062.

Adding to 164821520 its reverse (25128461), we get a palindrome (189949981).

The spelling of 164821520 in words is "one hundred sixty-four million, eight hundred twenty-one thousand, five hundred twenty".