20751047 has 2 divisors, whose sum is σ = 20751048. Its totient is φ = 20751046.

The previous prime is 20751023. The next prime is 20751061. The reversal of 20751047 is 74015702.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20751047 - 2¹⁴ = 20734663 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20751077) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10375523 + 10375524.

It is an arithmetic number, because the mean of its divisors is an integer number (10375524).

Almost surely, 2^20751047 is an apocalyptic number.

20751047 is a deficient number, since it is larger than the sum of its proper divisors (1).

20751047 is an equidigital number, since it uses as much as digits as its factorization.

20751047 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1960, while the sum is 26.

The square root of 20751047 is about 4555.3317113027. The cubic root of 20751047 is about 274.7978547506.

Adding to 20751047 its reverse (74015702), we get a palindrome (94766749).

The spelling of 20751047 in words is "twenty million, seven hundred fifty-one thousand, forty-seven".