20211345 has 96 divisors (see below), whose sum is σ = 46126080. Its totient is φ = 7931520.

The previous prime is 20211263. The next prime is 20211377. The reversal of 20211345 is 54311202.

It is not a de Polignac number, because 20211345 - 2¹¹ = 20209297 is a prime.

It is a Curzon number.

It is an unprimeable number.

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 95 ways as a sum of consecutive naturals, for example, 65682 + ... + 65988.

It is an arithmetic number, because the mean of its divisors is an integer number (480480).

Almost surely, 2^20211345 is an apocalyptic number.

It is an amenable number.

20211345 is an abundant number, since it is smaller than the sum of its proper divisors (25914735).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20211345 is a wasteful number, since it uses less digits than its factorization.

20211345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 355 (or 352 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 20211345 is about 4495.7029483719. The cubic root of 20211345 is about 272.3945443867.

Adding to 20211345 its reverse (54311202), we get a palindrome (74522547).

The spelling of 20211345 in words is "twenty million, two hundred eleven thousand, three hundred forty-five".