21255456103 has 4 divisors (see below), whose sum is σ = 24291949840. Its totient is φ = 18218962368.

The previous prime is 21255456097. The next prime is 21255456107. The reversal of 21255456103 is 30165455212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21255456103 - 2¹⁷ = 21255325031 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21255456107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1518246858 + ... + 1518246871.

It is an arithmetic number, because the mean of its divisors is an integer number (6072987460).

Almost surely, 2^21255456103 is an apocalyptic number.

21255456103 is a deficient number, since it is larger than the sum of its proper divisors (3036493737).

21255456103 is an equidigital number, since it uses as much as digits as its factorization.

21255456103 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3036493736.

The product of its (nonzero) digits is 36000, while the sum is 34.

The spelling of 21255456103 in words is "twenty-one billion, two hundred fifty-five million, four hundred fifty-six thousand, one hundred three".