164639425 has 6 divisors (see below), whose sum is σ = 204152918. Its totient is φ = 131711520.

The previous prime is 164639417. The next prime is 164639437. The reversal of 164639425 is 524936461.

It can be written as a sum of positive squares in 3 ways, for example, as 45589504 + 119049921 = 6752^2 + 10911^2 .

It is not a de Polignac number, because 164639425 - 2³ = 164639417 is a prime.

It is a super-2 number, since 2×164639425² = 54212280528661250, which contains 22 as substring.

It is a Duffinian 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 5 ways as a sum of consecutive naturals, for example, 3292764 + ... + 3292813.

Almost surely, 2^164639425 is an apocalyptic number.

It is an amenable number.

164639425 is a deficient number, since it is larger than the sum of its proper divisors (39513493).

164639425 is an equidigital number, since it uses as much as digits as its factorization.

164639425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6585587 (or 6585582 counting only the distinct ones).

The product of its digits is 155520, while the sum is 40.

The square root of 164639425 is about 12831.1895395556. The cubic root of 164639425 is about 548.0808317105.

The spelling of 164639425 in words is "one hundred sixty-four million, six hundred thirty-nine thousand, four hundred twenty-five".