21017010055 has 8 divisors (see below), whose sum is σ = 25295252112. Its totient is φ = 16763714688.

The previous prime is 21017010043. The next prime is 21017010073. The reversal of 21017010055 is 55001071012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21017010055 - 2²⁹ = 20480139143 is a prime.

It is a super-2 number, since 2×21017010055² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 6234817 + ... + 6238186.

It is an arithmetic number, because the mean of its divisors is an integer number (3161906514).

Almost surely, 2^21017010055 is an apocalyptic number.

21017010055 is a deficient number, since it is larger than the sum of its proper divisors (4278242057).

21017010055 is a wasteful number, since it uses less digits than its factorization.

21017010055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12473345.

The product of its (nonzero) digits is 350, while the sum is 22.

Adding to 21017010055 its reverse (55001071012), we get a palindrome (76018081067).

The spelling of 21017010055 in words is "twenty-one billion, seventeen million, ten thousand, fifty-five".