20788681 has 8 divisors (see below), whose sum is σ = 21385728. Its totient is φ = 20196000.

The previous prime is 20788673. The next prime is 20788687. The reversal of 20788681 is 18688702.

20788681 is nontrivially palindromic in base 8.

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

It is a cyclic number.

It is not a de Polignac number, because 20788681 - 2³ = 20788673 is a prime.

It is a super-2 number, since 2×20788681² = 864338515439522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20788687) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10176 + ... + 12046.

It is an arithmetic number, because the mean of its divisors is an integer number (2673216).

Almost surely, 2^20788681 is an apocalyptic number.

It is an amenable number.

20788681 is a deficient number, since it is larger than the sum of its proper divisors (597047).

20788681 is a wasteful number, since it uses less digits than its factorization.

20788681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2183.

The product of its (nonzero) digits is 43008, while the sum is 40.

The square root of 20788681 is about 4559.4606040627. The cubic root of 20788681 is about 274.9638784512.

It can be divided in two parts, 207 and 88681, that added together give a palindrome (88888).

The spelling of 20788681 in words is "twenty million, seven hundred eighty-eight thousand, six hundred eighty-one".