20633681 has 8 divisors (see below), whose sum is σ = 20978880. Its totient is φ = 20291472.

The previous prime is 20633663. The next prime is 20633729. The reversal of 20633681 is 18633602.

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 20633681 - 2⁶ = 20633617 is a prime.

It is a super-2 number, since 2×20633681² = 851497583219522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20633651) 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, 16175 + ... + 17403.

It is an arithmetic number, because the mean of its divisors is an integer number (2622360).

Almost surely, 2^20633681 is an apocalyptic number.

It is an amenable number.

20633681 is a deficient number, since it is larger than the sum of its proper divisors (345199).

20633681 is a wasteful number, since it uses less digits than its factorization.

20633681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1495.

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 20633681 is about 4542.4311772442. The cubic root of 20633681 is about 274.2787978658.

The spelling of 20633681 in words is "twenty million, six hundred thirty-three thousand, six hundred eighty-one".