20120155 has 16 divisors (see below), whose sum is σ = 26438400. Its totient is φ = 14577760.

The previous prime is 20120153. The next prime is 20120161. The reversal of 20120155 is 55102102.

20120155 = 372² + 373² + ... + 481².

It is not a de Polignac number, because 20120155 - 2¹ = 20120153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20120153) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 19236 + ... + 20254.

It is an arithmetic number, because the mean of its divisors is an integer number (1652400).

Almost surely, 2^20120155 is an apocalyptic number.

20120155 is a deficient number, since it is larger than the sum of its proper divisors (6318245).

20120155 is a wasteful number, since it uses less digits than its factorization.

20120155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1394.

The product of its (nonzero) digits is 100, while the sum is 16.

The square root of 20120155 is about 4485.5495761389. The cubic root of 20120155 is about 271.9842614524.

Adding to 20120155 its reverse (55102102), we get a palindrome (75222257).

The spelling of 20120155 in words is "twenty million, one hundred twenty thousand, one hundred fifty-five".