20072681 has 2 divisors, whose sum is σ = 20072682. Its totient is φ = 20072680.

The previous prime is 20072651. The next prime is 20072707. The reversal of 20072681 is 18627002.

It is an a-pointer prime, because the next prime (20072707) can be obtained adding 20072681 to its sum of digits (26).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14592400 + 5480281 = 3820^2 + 2341^2 .

It is a cyclic number.

It is not a de Polignac number, because 20072681 - 2⁶ = 20072617 is a prime.

It is a super-2 number, since 2×20072681² = 805825045055522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20072681.

It is not a weakly prime, because it can be changed into another prime (20072621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10036340 + 10036341.

It is an arithmetic number, because the mean of its divisors is an integer number (10036341).

Almost surely, 2^20072681 is an apocalyptic number.

It is an amenable number.

20072681 is a deficient number, since it is larger than the sum of its proper divisors (1).

20072681 is an equidigital number, since it uses as much as digits as its factorization.

20072681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1344, while the sum is 26.

The square root of 20072681 is about 4480.2545686601. The cubic root of 20072681 is about 271.7701751345.

Adding to 20072681 its reverse (18627002), we get a palindrome (38699683).

The spelling of 20072681 in words is "twenty million, seventy-two thousand, six hundred eighty-one".