20212155 has 24 divisors (see below), whose sum is σ = 36167040. Its totient is φ = 10431360.

The previous prime is 20212151. The next prime is 20212183. The reversal of 20212155 is 55121202.

It is not a de Polignac number, because 20212155 - 2² = 20212151 is a prime.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20212151) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5850 + ... + 8639.

It is an arithmetic number, because the mean of its divisors is an integer number (1506960).

Almost surely, 2^20212155 is an apocalyptic number.

20212155 is a deficient number, since it is larger than the sum of its proper divisors (15954885).

20212155 is a wasteful number, since it uses less digits than its factorization.

20212155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14531 (or 14528 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 18.

The square root of 20212155 is about 4495.7930334925. The cubic root of 20212155 is about 272.3981832116.

Adding to 20212155 its reverse (55121202), we get a palindrome (75333357).

The spelling of 20212155 in words is "twenty million, two hundred twelve thousand, one hundred fifty-five".