21392128873 has 2 divisors, whose sum is σ = 21392128874. Its totient is φ = 21392128872.

The previous prime is 21392128847. The next prime is 21392128907. The reversal of 21392128873 is 37882129312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11632269609 + 9759859264 = 107853^2 + 98792^2 .

It is a cyclic number.

It is not a de Polignac number, because 21392128873 - 2⁵ = 21392128841 is a prime.

It is not a weakly prime, because it can be changed into another prime (21392128843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10696064436 + 10696064437.

It is an arithmetic number, because the mean of its divisors is an integer number (10696064437).

Almost surely, 2^21392128873 is an apocalyptic number.

It is an amenable number.

21392128873 is a deficient number, since it is larger than the sum of its proper divisors (1).

21392128873 is an equidigital number, since it uses as much as digits as its factorization.

21392128873 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 290304, while the sum is 46.

The spelling of 21392128873 in words is "twenty-one billion, three hundred ninety-two million, one hundred twenty-eight thousand, eight hundred seventy-three".