21441370765 has 4 divisors (see below), whose sum is σ = 25729644924. Its totient is φ = 17153096608.

The previous prime is 21441370739. The next prime is 21441370793. The reversal of 21441370765 is 56707314412.

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 10123176996 + 11318193769 = 100614^2 + 106387^2 .

It is a cyclic number.

It is not a de Polignac number, because 21441370765 - 2¹⁵ = 21441337997 is a prime.

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 (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2144137072 + ... + 2144137081.

It is an arithmetic number, because the mean of its divisors is an integer number (6432411231).

Almost surely, 2^21441370765 is an apocalyptic number.

It is an amenable number.

21441370765 is a deficient number, since it is larger than the sum of its proper divisors (4288274159).

21441370765 is an equidigital number, since it uses as much as digits as its factorization.

21441370765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4288274158.

The product of its (nonzero) digits is 141120, while the sum is 40.

The spelling of 21441370765 in words is "twenty-one billion, four hundred forty-one million, three hundred seventy thousand, seven hundred sixty-five".