20647245 has 16 divisors (see below), whose sum is σ = 33206400. Its totient is φ = 10954944.

The previous prime is 20647229. The next prime is 20647273. The reversal of 20647245 is 54274602.

It is not a de Polignac number, because 20647245 - 2⁴ = 20647229 is a prime.

It is a congruent number.

It is an unprimeable number.

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, 474 + ... + 6443.

It is an arithmetic number, because the mean of its divisors is an integer number (2075400).

Almost surely, 2^20647245 is an apocalyptic number.

It is an amenable number.

20647245 is a deficient number, since it is larger than the sum of its proper divisors (12559155).

20647245 is a wasteful number, since it uses less digits than its factorization.

20647245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7124.

The product of its (nonzero) digits is 13440, while the sum is 30.

The square root of 20647245 is about 4543.9239650329. The cubic root of 20647245 is about 274.3388857499.

The spelling of 20647245 in words is "twenty million, six hundred forty-seven thousand, two hundred forty-five".