164399625 has 80 divisors (see below), whose sum is σ = 330330000. Its totient is φ = 80870400.

The previous prime is 164399617. The next prime is 164399633. The reversal of 164399625 is 526993461.

164399625 is a `hidden beast` number, since 16 + 4 + 3 + 9 + 9 + 625 = 666.

It is an interprime number because it is at equal distance from previous prime (164399617) and next prime (164399633).

It can be written as a sum of positive squares in 8 ways, for example, as 92217609 + 72182016 = 9603^2 + 8496^2 .

It is not a de Polignac number, because 164399625 - 2³ = 164399617 is a prime.

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 (11) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 131001 + ... + 132249.

It is an arithmetic number, because the mean of its divisors is an integer number (4129125).

Almost surely, 2^164399625 is an apocalyptic number.

164399625 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

164399625 is an abundant number, since it is smaller than the sum of its proper divisors (165930375).

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

164399625 is a wasteful number, since it uses less digits than its factorization.

164399625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1289 (or 1270 counting only the distinct ones).

The product of its digits is 349920, while the sum is 45.

The square root of 164399625 is about 12821.8417163838. The cubic root of 164399625 is about 547.8146061998.

The spelling of 164399625 in words is "one hundred sixty-four million, three hundred ninety-nine thousand, six hundred twenty-five".