164821025 has 18 divisors (see below), whose sum is σ = 209886306. Its totient is φ = 128320000.

The previous prime is 164821003. The next prime is 164821037. The reversal of 164821025 is 520128461.

It can be written as a sum of positive squares in 9 ways, for example, as 2819041 + 162001984 = 1679^2 + 12728^2 .

It is not a de Polignac number, because 164821025 - 2⁶ = 164820961 is a prime.

It is a Duffinian number.

It is a congruent number.

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 17 ways as a sum of consecutive naturals, for example, 410825 + ... + 411225.

Almost surely, 2^164821025 is an apocalyptic number.

It is an amenable number.

164821025 is a deficient number, since it is larger than the sum of its proper divisors (45065281).

164821025 is an frugal number, since it uses more digits than its factorization.

164821025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 853 (or 447 counting only the distinct ones).

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

The square root of 164821025 is about 12838.2640960529. The cubic root of 164821025 is about 548.2822717291.

Adding to 164821025 its reverse (520128461), we get a palindrome (684949486).

The spelling of 164821025 in words is "one hundred sixty-four million, eight hundred twenty-one thousand, twenty-five".