20645345 has 16 divisors (see below), whose sum is σ = 29006208. Its totient is φ = 13810560.

The previous prime is 20645341. The next prime is 20645347. The reversal of 20645345 is 54354602.

It is not a de Polignac number, because 20645345 - 2² = 20645341 is a prime.

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

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5759 + ... + 8628.

It is an arithmetic number, because the mean of its divisors is an integer number (1812888).

Almost surely, 2^20645345 is an apocalyptic number.

It is an amenable number.

20645345 is a deficient number, since it is larger than the sum of its proper divisors (8360863).

20645345 is a wasteful number, since it uses less digits than its factorization.

20645345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14440.

The product of its (nonzero) digits is 14400, while the sum is 29.

The square root of 20645345 is about 4543.7148898231. The cubic root of 20645345 is about 274.3304704242.

Adding to 20645345 its reverse (54354602), we get a palindrome (74999947).

The spelling of 20645345 in words is "twenty million, six hundred forty-five thousand, three hundred forty-five".