212106155 has 4 divisors (see below), whose sum is σ = 254527392. Its totient is φ = 169684920.

The previous prime is 212106151. The next prime is 212106197. The reversal of 212106155 is 551601212.

It is a happy number.

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

It is not a de Polignac number, because 212106155 - 2² = 212106151 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 212106155.

It is not an unprimeable number, because it can be changed into a prime (212106151) 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, 21210611 + ... + 21210620.

It is an arithmetic number, because the mean of its divisors is an integer number (63631848).

Almost surely, 2^212106155 is an apocalyptic number.

212106155 is a deficient number, since it is larger than the sum of its proper divisors (42421237).

212106155 is an equidigital number, since it uses as much as digits as its factorization.

212106155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42421236.

The product of its (nonzero) digits is 600, while the sum is 23.

The square root of 212106155 is about 14563.8647000032. The cubic root of 212106155 is about 596.3727033515.

Adding to 212106155 its reverse (551601212), we get a palindrome (763707367).

The spelling of 212106155 in words is "two hundred twelve million, one hundred six thousand, one hundred fifty-five".