21870750305 has 4 divisors (see below), whose sum is σ = 26244900372. Its totient is φ = 17496600240.

The previous prime is 21870750277. The next prime is 21870750323. The reversal of 21870750305 is 50305707812.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 16536931216 + 5333819089 = 128596^2 + 73033^2 .

It is not a de Polignac number, because 21870750305 - 2¹⁰ = 21870749281 is a prime.

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, 2187075026 + ... + 2187075035.

It is an arithmetic number, because the mean of its divisors is an integer number (6561225093).

Almost surely, 2^21870750305 is an apocalyptic number.

It is an amenable number.

21870750305 is a deficient number, since it is larger than the sum of its proper divisors (4374150067).

21870750305 is an equidigital number, since it uses as much as digits as its factorization.

21870750305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4374150066.

The product of its (nonzero) digits is 58800, while the sum is 38.

The spelling of 21870750305 in words is "twenty-one billion, eight hundred seventy million, seven hundred fifty thousand, three hundred five".