21559078253 has 2 divisors, whose sum is σ = 21559078254. Its totient is φ = 21559078252.

The previous prime is 21559078249. The next prime is 21559078319. The reversal of 21559078253 is 35287095512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14131741129 + 7427337124 = 118877^2 + 86182^2 .

It is a cyclic number.

It is not a de Polignac number, because 21559078253 - 2² = 21559078249 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21559078198 and 21559078207.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21559078223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10779539126 + 10779539127.

It is an arithmetic number, because the mean of its divisors is an integer number (10779539127).

Almost surely, 2^21559078253 is an apocalyptic number.

It is an amenable number.

21559078253 is a deficient number, since it is larger than the sum of its proper divisors (1).

21559078253 is an equidigital number, since it uses as much as digits as its factorization.

21559078253 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 756000, while the sum is 47.

The spelling of 21559078253 in words is "twenty-one billion, five hundred fifty-nine million, seventy-eight thousand, two hundred fifty-three".