21020704273 has 4 divisors (see below), whose sum is σ = 21022603888. Its totient is φ = 21018804660.

The previous prime is 21020704261. The next prime is 21020704333. The reversal of 21020704273 is 37240702012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21020704273 - 2¹⁷ = 21020573201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21020704073) 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, 933111 + ... + 955372.

It is an arithmetic number, because the mean of its divisors is an integer number (5255650972).

Almost surely, 2^21020704273 is an apocalyptic number.

It is an amenable number.

21020704273 is a deficient number, since it is larger than the sum of its proper divisors (1899615).

21020704273 is a wasteful number, since it uses less digits than its factorization.

21020704273 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1899614.

The product of its (nonzero) digits is 4704, while the sum is 28.

The spelling of 21020704273 in words is "twenty-one billion, twenty million, seven hundred four thousand, two hundred seventy-three".