20121055 has 4 divisors (see below), whose sum is σ = 24145272. Its totient is φ = 16096840.

The previous prime is 20121043. The next prime is 20121061. The reversal of 20121055 is 55012102.

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

It is not a de Polignac number, because 20121055 - 2⁷ = 20120927 is a prime.

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, 2012101 + ... + 2012110.

It is an arithmetic number, because the mean of its divisors is an integer number (6036318).

Almost surely, 2^20121055 is an apocalyptic number.

20121055 is a deficient number, since it is larger than the sum of its proper divisors (4024217).

20121055 is an equidigital number, since it uses as much as digits as its factorization.

20121055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4024216.

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

The square root of 20121055 is about 4485.6498971721. The cubic root of 20121055 is about 271.9883167920.

Adding to 20121055 its reverse (55012102), we get a palindrome (75133157).

It can be divided in two parts, 20 and 121055, that multiplied together give a triangular number (2421100 = T₂₂₀₀).

The spelling of 20121055 in words is "twenty million, one hundred twenty-one thousand, fifty-five".