20553887 has 2 divisors, whose sum is σ = 20553888. Its totient is φ = 20553886.

The previous prime is 20553853. The next prime is 20553893. The reversal of 20553887 is 78835502.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20553887 - 2⁶ = 20553823 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20553887.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20553847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10276943 + 10276944.

It is an arithmetic number, because the mean of its divisors is an integer number (10276944).

Almost surely, 2^20553887 is an apocalyptic number.

20553887 is a deficient number, since it is larger than the sum of its proper divisors (1).

20553887 is an equidigital number, since it uses as much as digits as its factorization.

20553887 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 67200, while the sum is 38.

The square root of 20553887 is about 4533.6394872111. The cubic root of 20553887 is about 273.9247799985.

The spelling of 20553887 in words is "twenty million, five hundred fifty-three thousand, eight hundred eighty-seven".