20212005 has 16 divisors (see below), whose sum is σ = 35279424. Its totient is φ = 9799680.

The previous prime is 20212001. The next prime is 20212013. The reversal of 20212005 is 50021202.

It is not a de Polignac number, because 20212005 - 2² = 20212001 is a prime.

It is a super-2 number, since 2×20212005² = 817050292240050, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20212001) 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, 61084 + ... + 61413.

It is an arithmetic number, because the mean of its divisors is an integer number (2204964).

Almost surely, 2^20212005 is an apocalyptic number.

It is an amenable number.

20212005 is a deficient number, since it is larger than the sum of its proper divisors (15067419).

20212005 is a wasteful number, since it uses less digits than its factorization.

20212005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122516.

The product of its (nonzero) digits is 40, while the sum is 12.

The square root of 20212005 is about 4495.7763511990. The cubic root of 20212005 is about 272.3975093624.

Adding to 20212005 its reverse (50021202), we get a palindrome (70233207).

The spelling of 20212005 in words is "twenty million, two hundred twelve thousand, five".