20669553 has 8 divisors (see below), whose sum is σ = 30621600. Its totient is φ = 13779684.

The previous prime is 20669543. The next prime is 20669563. The reversal of 20669553 is 35596602.

It is an interprime number because it is at equal distance from previous prime (20669543) and next prime (20669563).

It is not a de Polignac number, because 20669553 - 2⁹ = 20669041 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20669513) 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 in 7 ways as a sum of consecutive naturals, for example, 382743 + ... + 382796.

It is an arithmetic number, because the mean of its divisors is an integer number (3827700).

Almost surely, 2^20669553 is an apocalyptic number.

It is an amenable number.

20669553 is a deficient number, since it is larger than the sum of its proper divisors (9952047).

20669553 is an equidigital number, since it uses as much as digits as its factorization.

20669553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 765548 (or 765542 counting only the distinct ones).

The product of its (nonzero) digits is 48600, while the sum is 36.

The square root of 20669553 is about 4546.3780089209. The cubic root of 20669553 is about 274.4376519391.

The spelling of 20669553 in words is "twenty million, six hundred sixty-nine thousand, five hundred fifty-three".