20302681 has 4 divisors (see below), whose sum is σ = 23203072. Its totient is φ = 17402292.

The previous prime is 20302649. The next prime is 20302693. The reversal of 20302681 is 18620302.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18620302 = 2 ⋅9310151.

It is a cyclic number.

It is not a de Polignac number, because 20302681 - 2⁵ = 20302649 is a prime.

It is a super-2 number, since 2×20302681² = 824397711575522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20302481) 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, 1450185 + ... + 1450198.

It is an arithmetic number, because the mean of its divisors is an integer number (5800768).

Almost surely, 2^20302681 is an apocalyptic number.

It is an amenable number.

20302681 is a deficient number, since it is larger than the sum of its proper divisors (2900391).

20302681 is an equidigital number, since it uses as much as digits as its factorization.

20302681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2900390.

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 20302681 is about 4505.8496424093. The cubic root of 20302681 is about 272.8042490158.

Adding to 20302681 its reverse (18620302), we get a palindrome (38922983).

The spelling of 20302681 in words is "twenty million, three hundred two thousand, six hundred eighty-one".