21551470459 has 2 divisors, whose sum is σ = 21551470460. Its totient is φ = 21551470458.

The previous prime is 21551470337. The next prime is 21551470481. The reversal of 21551470459 is 95407415512.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21551470459 - 2⁷ = 21551470331 is a prime.

It is not a weakly prime, because it can be changed into another prime (21551470859) 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, 10775735229 + 10775735230.

It is an arithmetic number, because the mean of its divisors is an integer number (10775735230).

Almost surely, 2^21551470459 is an apocalyptic number.

21551470459 is a deficient number, since it is larger than the sum of its proper divisors (1).

21551470459 is an equidigital number, since it uses as much as digits as its factorization.

21551470459 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 252000, while the sum is 43.

The spelling of 21551470459 in words is "twenty-one billion, five hundred fifty-one million, four hundred seventy thousand, four hundred fifty-nine".