20516705 has 16 divisors (see below), whose sum is σ = 28439424. Its totient is φ = 14042880.

The previous prime is 20516693. The next prime is 20516707. The reversal of 20516705 is 50761502.

It is not a de Polignac number, because 20516705 - 2⁴ = 20516689 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20516707) 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, 10037 + ... + 11906.

It is an arithmetic number, because the mean of its divisors is an integer number (1777464).

Almost surely, 2^20516705 is an apocalyptic number.

It is an amenable number.

20516705 is a deficient number, since it is larger than the sum of its proper divisors (7922719).

20516705 is a wasteful number, since it uses less digits than its factorization.

20516705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21976.

The product of its (nonzero) digits is 2100, while the sum is 26.

The square root of 20516705 is about 4529.5369520515. The cubic root of 20516705 is about 273.7595035725.

The spelling of 20516705 in words is "twenty million, five hundred sixteen thousand, seven hundred five".