21551503219 has 2 divisors, whose sum is σ = 21551503220. Its totient is φ = 21551503218.

The previous prime is 21551503213. The next prime is 21551503223. The reversal of 21551503219 is 91230515512.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21551503219 is a prime.

It is a super-2 number, since 2×21551503219² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21551503213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10775751609 + 10775751610.

It is an arithmetic number, because the mean of its divisors is an integer number (10775751610).

Almost surely, 2^21551503219 is an apocalyptic number.

21551503219 is a deficient number, since it is larger than the sum of its proper divisors (1).

21551503219 is an equidigital number, since it uses as much as digits as its factorization.

21551503219 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13500, while the sum is 34.

The spelling of 21551503219 in words is "twenty-one billion, five hundred fifty-one million, five hundred three thousand, two hundred nineteen".