20655869 has 16 divisors (see below), whose sum is σ = 23580480. Its totient is φ = 17936640.

The previous prime is 20655857. The next prime is 20655871. The reversal of 20655869 is 96855602.

It is a cyclic number.

It is not a de Polignac number, because 20655869 - 2⁴ = 20655853 is a prime.

It is a super-2 number, since 2×20655869² = 853329848290322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20655829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 59354 + ... + 59700.

It is an arithmetic number, because the mean of its divisors is an integer number (1473780).

Almost surely, 2^20655869 is an apocalyptic number.

It is an amenable number.

20655869 is a deficient number, since it is larger than the sum of its proper divisors (2924611).

20655869 is a wasteful number, since it uses less digits than its factorization.

20655869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 620.

The product of its (nonzero) digits is 129600, while the sum is 41.

The square root of 20655869 is about 4544.8728255035. The cubic root of 20655869 is about 274.3770759819.

The spelling of 20655869 in words is "twenty million, six hundred fifty-five thousand, eight hundred sixty-nine".