20988893 has 2 divisors, whose sum is σ = 20988894. Its totient is φ = 20988892.

The previous prime is 20988881. The next prime is 20988907. The reversal of 20988893 is 39888902.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18292729 + 2696164 = 4277^2 + 1642^2 .

It is a cyclic number.

It is not a de Polignac number, because 20988893 - 2⁸ = 20988637 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20988823) 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 as a sum of consecutive naturals, namely, 10494446 + 10494447.

It is an arithmetic number, because the mean of its divisors is an integer number (10494447).

Almost surely, 2^20988893 is an apocalyptic number.

It is an amenable number.

20988893 is a deficient number, since it is larger than the sum of its proper divisors (1).

20988893 is an equidigital number, since it uses as much as digits as its factorization.

20988893 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 248832, while the sum is 47.

The square root of 20988893 is about 4581.3636616187. The cubic root of 20988893 is about 275.8437687891.

The spelling of 20988893 in words is "twenty million, nine hundred eighty-eight thousand, eight hundred ninety-three".