20677647 has 4 divisors (see below), whose sum is σ = 27570200. Its totient is φ = 13785096.

The previous prime is 20677639. The next prime is 20677649. The reversal of 20677647 is 74677602.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 20677647 - 2³ = 20677639 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20677649) 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, 3446272 + ... + 3446277.

It is an arithmetic number, because the mean of its divisors is an integer number (6892550).

Almost surely, 2^20677647 is an apocalyptic number.

20677647 is a deficient number, since it is larger than the sum of its proper divisors (6892553).

20677647 is an equidigital number, since it uses as much as digits as its factorization.

20677647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6892552.

The product of its (nonzero) digits is 98784, while the sum is 39.

The square root of 20677647 is about 4547.2680809471. The cubic root of 20677647 is about 274.4734696540.

The spelling of 20677647 in words is "twenty million, six hundred seventy-seven thousand, six hundred forty-seven".