20645349 has 16 divisors (see below), whose sum is σ = 28813824. Its totient is φ = 13132800.

The previous prime is 20645347. The next prime is 20645399. The reversal of 20645349 is 94354602.

It is not a de Polignac number, because 20645349 - 2¹ = 20645347 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20645341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5269 + ... + 8309.

It is an arithmetic number, because the mean of its divisors is an integer number (1800864).

Almost surely, 2^20645349 is an apocalyptic number.

It is an amenable number.

20645349 is a deficient number, since it is larger than the sum of its proper divisors (8168475).

20645349 is a wasteful number, since it uses less digits than its factorization.

20645349 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3148.

The product of its (nonzero) digits is 25920, while the sum is 33.

The square root of 20645349 is about 4543.7153299915. The cubic root of 20645349 is about 274.3304881413.

The spelling of 20645349 in words is "twenty million, six hundred forty-five thousand, three hundred forty-nine".