20745655 has 16 divisors (see below), whose sum is σ = 29689344. Its totient is φ = 13606560.

The previous prime is 20745649. The next prime is 20745667. The reversal of 20745655 is 55654702.

It is not a de Polignac number, because 20745655 - 2⁵ = 20745623 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20745655.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12081 + ... + 13690.

It is an arithmetic number, because the mean of its divisors is an integer number (1855584).

Almost surely, 2^20745655 is an apocalyptic number.

20745655 is a deficient number, since it is larger than the sum of its proper divisors (8943689).

20745655 is a wasteful number, since it uses less digits than its factorization.

20745655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25806.

The product of its (nonzero) digits is 42000, while the sum is 34.

The square root of 20745655 is about 4554.7398388931. The cubic root of 20745655 is about 274.7740513189.

The spelling of 20745655 in words is "twenty million, seven hundred forty-five thousand, six hundred fifty-five".