20280751 has 2 divisors, whose sum is σ = 20280752. Its totient is φ = 20280750.

The previous prime is 20280749. The next prime is 20280761. The reversal of 20280751 is 15708202.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20280751 - 2¹ = 20280749 is a prime.

It is a super-3 number, since 3×20280751³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

Together with 20280749, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20280721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10140375 + 10140376.

It is an arithmetic number, because the mean of its divisors is an integer number (10140376).

Almost surely, 2^20280751 is an apocalyptic number.

20280751 is a deficient number, since it is larger than the sum of its proper divisors (1).

20280751 is an equidigital number, since it uses as much as digits as its factorization.

20280751 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1120, while the sum is 25.

The square root of 20280751 is about 4503.4154816095. The cubic root of 20280751 is about 272.7059901945.

Adding to 20280751 its reverse (15708202), we get a palindrome (35988953).

The spelling of 20280751 in words is "twenty million, two hundred eighty thousand, seven hundred fifty-one".