20659481 has 4 divisors (see below), whose sum is σ = 20891700. Its totient is φ = 20427264.

The previous prime is 20659427. The next prime is 20659493. The reversal of 20659481 is 18495602.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18495602 = 2 ⋅9247801.

It can be written as a sum of positive squares in 2 ways, for example, as 2298256 + 18361225 = 1516^2 + 4285^2 .

It is a cyclic number.

It is not a de Polignac number, because 20659481 - 2⁶ = 20659417 is a prime.

It is a super-2 number, since 2×20659481² = 853628310378722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20659421) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 115976 + ... + 116153.

It is an arithmetic number, because the mean of its divisors is an integer number (5222925).

Almost surely, 2^20659481 is an apocalyptic number.

It is an amenable number.

20659481 is a deficient number, since it is larger than the sum of its proper divisors (232219).

20659481 is an equidigital number, since it uses as much as digits as its factorization.

20659481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 232218.

The product of its (nonzero) digits is 17280, while the sum is 35.

The square root of 20659481 is about 4545.2701789883. The cubic root of 20659481 is about 274.3930680830.

The spelling of 20659481 in words is "twenty million, six hundred fifty-nine thousand, four hundred eighty-one".