20261686 has 8 divisors (see below), whose sum is σ = 31099464. Its totient is φ = 9895200.

The previous prime is 20261629. The next prime is 20261687. The reversal of 20261686 is 68616202.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20261687) 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 3 ways as a sum of consecutive naturals, for example, 117715 + ... + 117886.

It is an arithmetic number, because the mean of its divisors is an integer number (3887433).

Almost surely, 2^20261686 is an apocalyptic number.

20261686 is a deficient number, since it is larger than the sum of its proper divisors (10837778).

20261686 is a wasteful number, since it uses less digits than its factorization.

20261686 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 235646.

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 20261686 is about 4501.2982571698. The cubic root of 20261686 is about 272.6205106230.

Adding to 20261686 its reverse (68616202), we get a palindrome (88877888).

The spelling of 20261686 in words is "twenty million, two hundred sixty-one thousand, six hundred eighty-six".