20172560 has 20 divisors (see below), whose sum is σ = 46901388. Its totient is φ = 8068992.

The previous prime is 20172539. The next prime is 20172563. The reversal of 20172560 is 6527102.

It can be written as a sum of positive squares in 2 ways, for example, as 14992384 + 5180176 = 3872^2 + 2276^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is not an unprimeable number, because it can be changed into a prime (20172563) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 125999 + ... + 126158.

Almost surely, 2^20172560 is an apocalyptic number.

20172560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20172560 is an abundant number, since it is smaller than the sum of its proper divisors (26728828).

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

20172560 is a wasteful number, since it uses less digits than its factorization.

20172560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 252170 (or 252164 counting only the distinct ones).

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 20172560 is about 4491.3873135146. The cubic root of 20172560 is about 272.2201936696.

Adding to 20172560 its reverse (6527102), we get a palindrome (26699662).

The spelling of 20172560 in words is "twenty million, one hundred seventy-two thousand, five hundred sixty".