20890137973 has 2 divisors, whose sum is σ = 20890137974. Its totient is φ = 20890137972.

The previous prime is 20890137937. The next prime is 20890138037. The reversal of 20890137973 is 37973109802.

Together with previous prime (20890137937) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18371904849 + 2518233124 = 135543^2 + 50182^2 .

It is a cyclic number.

It is not a de Polignac number, because 20890137973 - 2¹³ = 20890129781 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20890137173) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10445068986 + 10445068987.

It is an arithmetic number, because the mean of its divisors is an integer number (10445068987).

Almost surely, 2^20890137973 is an apocalyptic number.

It is an amenable number.

20890137973 is a deficient number, since it is larger than the sum of its proper divisors (1).

20890137973 is an equidigital number, since it uses as much as digits as its factorization.

20890137973 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 571536, while the sum is 49.

The spelling of 20890137973 in words is "twenty billion, eight hundred ninety million, one hundred thirty-seven thousand, nine hundred seventy-three".