20788663 has 4 divisors (see below), whose sum is σ = 23758480. Its totient is φ = 17818848.

The previous prime is 20788657. The next prime is 20788673. The reversal of 20788663 is 36688702.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 20788663 - 2¹⁷ = 20657591 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 (20788633) 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, 1484898 + ... + 1484911.

It is an arithmetic number, because the mean of its divisors is an integer number (5939620).

Almost surely, 2^20788663 is an apocalyptic number.

20788663 is a deficient number, since it is larger than the sum of its proper divisors (2969817).

20788663 is an equidigital number, since it uses as much as digits as its factorization.

20788663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2969816.

The product of its (nonzero) digits is 96768, while the sum is 40.

The square root of 20788663 is about 4559.4586301446. The cubic root of 20788663 is about 274.9637990915.

The spelling of 20788663 in words is "twenty million, seven hundred eighty-eight thousand, six hundred sixty-three".