20988663 has 8 divisors (see below), whose sum is σ = 28950000. Its totient is φ = 13509888.

The previous prime is 20988637. The next prime is 20988677. The reversal of 20988663 is 36688902.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20988663 - 2⁶ = 20988599 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20988613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 120538 + ... + 120711.

It is an arithmetic number, because the mean of its divisors is an integer number (3618750).

Almost surely, 2^20988663 is an apocalyptic number.

20988663 is a deficient number, since it is larger than the sum of its proper divisors (7961337).

20988663 is a wasteful number, since it uses less digits than its factorization.

20988663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 241281.

The product of its (nonzero) digits is 124416, while the sum is 42.

The square root of 20988663 is about 4581.3385598534. The cubic root of 20988663 is about 275.8427612038.

The spelling of 20988663 in words is "twenty million, nine hundred eighty-eight thousand, six hundred sixty-three".