20172055 has 4 divisors (see below), whose sum is σ = 24206472. Its totient is φ = 16137640.

The previous prime is 20172037. The next prime is 20172073. The reversal of 20172055 is 55027102.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (20172037) and next prime (20172073).

It is not a de Polignac number, because 20172055 - 2⁷ = 20171927 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2017201 + ... + 2017210.

It is an arithmetic number, because the mean of its divisors is an integer number (6051618).

Almost surely, 2^20172055 is an apocalyptic number.

20172055 is a deficient number, since it is larger than the sum of its proper divisors (4034417).

20172055 is an equidigital number, since it uses as much as digits as its factorization.

20172055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4034416.

The product of its (nonzero) digits is 700, while the sum is 22.

The square root of 20172055 is about 4491.3310944530. The cubic root of 20172055 is about 272.2179220633.

Adding to 20172055 its reverse (55027102), we get a palindrome (75199157).

The spelling of 20172055 in words is "twenty million, one hundred seventy-two thousand, fifty-five".