20666065 has 16 divisors (see below), whose sum is σ = 28435968. Its totient is φ = 14124096.

The previous prime is 20666047. The next prime is 20666077. The reversal of 20666065 is 56066602.

It is a de Polignac number, because none of the positive numbers 2^k-20666065 is a prime.

It is a Duffinian 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, 12264 + ... + 13846.

It is an arithmetic number, because the mean of its divisors is an integer number (1777248).

Almost surely, 2^20666065 is an apocalyptic number.

It is an amenable number.

20666065 is a deficient number, since it is larger than the sum of its proper divisors (7769903).

20666065 is a wasteful number, since it uses less digits than its factorization.

20666065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1968.

The product of its (nonzero) digits is 12960, while the sum is 31.

The square root of 20666065 is about 4545.9943906697. The cubic root of 20666065 is about 274.4222138955.

The spelling of 20666065 in words is "twenty million, six hundred sixty-six thousand, sixty-five".