21006142255 has 8 divisors (see below), whose sum is σ = 28808423712. Its totient is φ = 14404211808.

The previous prime is 21006142243. The next prime is 21006142277. The reversal of 21006142255 is 55224160012.

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

It is not a de Polignac number, because 21006142255 - 2¹⁹ = 21005617967 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 300087712 + ... + 300087781.

It is an arithmetic number, because the mean of its divisors is an integer number (3601052964).

Almost surely, 2^21006142255 is an apocalyptic number.

21006142255 is a deficient number, since it is larger than the sum of its proper divisors (7802281457).

21006142255 is an equidigital number, since it uses as much as digits as its factorization.

21006142255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 600175505.

The product of its (nonzero) digits is 4800, while the sum is 28.

The spelling of 21006142255 in words is "twenty-one billion, six million, one hundred forty-two thousand, two hundred fifty-five".