21577153231009 has 2 divisors, whose sum is σ = 21577153231010. Its totient is φ = 21577153231008.

The previous prime is 21577153230989. The next prime is 21577153231061. The reversal of 21577153231009 is 90013235177512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15193647797409 + 6383505433600 = 3897903^2 + 2526560^2 .

It is a cyclic number.

It is not a de Polignac number, because 21577153231009 - 2⁹ = 21577153230497 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21577153231009.

It is not a weakly prime, because it can be changed into another prime (21577153235009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10788576615504 + 10788576615505.

It is an arithmetic number, because the mean of its divisors is an integer number (10788576615505).

Almost surely, 2^{21577153231009} is an apocalyptic number.

It is an amenable number.

21577153231009 is a deficient number, since it is larger than the sum of its proper divisors (1).

21577153231009 is an equidigital number, since it uses as much as digits as its factorization.

21577153231009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 396900, while the sum is 46.

The spelling of 21577153231009 in words is "twenty-one trillion, five hundred seventy-seven billion, one hundred fifty-three million, two hundred thirty-one thousand, nine".