20172649 has 8 divisors (see below), whose sum is σ = 23094720. Its totient is φ = 17260656.

The previous prime is 20172643. The next prime is 20172667. The reversal of 20172649 is 94627102.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20172649 - 2³ = 20172641 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20172649.

It is not an unprimeable number, because it can be changed into a prime (20172641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2427 + ... + 6799.

It is an arithmetic number, because the mean of its divisors is an integer number (2886840).

Almost surely, 2^20172649 is an apocalyptic number.

It is an amenable number.

20172649 is a deficient number, since it is larger than the sum of its proper divisors (2922071).

20172649 is an equidigital number, since it uses as much as digits as its factorization.

20172649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5039.

The product of its (nonzero) digits is 6048, while the sum is 31.

The square root of 20172649 is about 4491.3972213555. The cubic root of 20172649 is about 272.2205940082.

The spelling of 20172649 in words is "twenty million, one hundred seventy-two thousand, six hundred forty-nine".