21046851073705 has 4 divisors (see below), whose sum is σ = 25256221288452. Its totient is φ = 16837480858960.

The previous prime is 21046851073687. The next prime is 21046851073723. The reversal of 21046851073705 is 50737015864012.

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

It is an interprime number because it is at equal distance from previous prime (21046851073687) and next prime (21046851073723).

It can be written as a sum of positive squares in 2 ways, for example, as 10367987844096 + 10678863229609 = 3219936^2 + 3267853^2 .

It is not a de Polignac number, because 21046851073705 - 2²¹ = 21046848976553 is a prime.

It is a super-2 number, since 2×21046851073705² (a number of 27 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2104685107366 + ... + 2104685107375.

It is an arithmetic number, because the mean of its divisors is an integer number (6314055322113).

Almost surely, 2^{21046851073705} is an apocalyptic number.

It is an amenable number.

21046851073705 is a deficient number, since it is larger than the sum of its proper divisors (4209370214747).

21046851073705 is an equidigital number, since it uses as much as digits as its factorization.

21046851073705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4209370214746.

The product of its (nonzero) digits is 1411200, while the sum is 49.

The spelling of 21046851073705 in words is "twenty-one trillion, forty-six billion, eight hundred fifty-one million, seventy-three thousand, seven hundred five".