20666677 has 4 divisors (see below), whose sum is σ = 21333376. Its totient is φ = 19999980.

The previous prime is 20666671. The next prime is 20666687. The reversal of 20666677 is 77666602.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20666677 - 2³ = 20666669 is a prime.

It is a super-2 number, since 2×20666677² = 854223076444658, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20666671) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 333303 + ... + 333364.

It is an arithmetic number, because the mean of its divisors is an integer number (5333344).

Almost surely, 2^20666677 is an apocalyptic number.

It is an amenable number.

20666677 is a deficient number, since it is larger than the sum of its proper divisors (666699).

20666677 is an equidigital number, since it uses as much as digits as its factorization.

20666677 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 666698.

The product of its (nonzero) digits is 127008, while the sum is 40.

The square root of 20666677 is about 4546.0617021770. The cubic root of 20666677 is about 274.4249227604.

The spelling of 20666677 in words is "twenty million, six hundred sixty-six thousand, six hundred seventy-seven".