21310610765 has 8 divisors (see below), whose sum is σ = 25574010360. Its totient is φ = 17047636992.

The previous prime is 21310610759. The next prime is 21310610779. The reversal of 21310610765 is 56701601312.

It can be written as a sum of positive squares in 4 ways, for example, as 7727640649 + 13582970116 = 87907^2 + 116546^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 21310610765 - 2⁴ = 21310610749 is a prime.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 16577 + ... + 207113.

It is an arithmetic number, because the mean of its divisors is an integer number (3196751295).

Almost surely, 2^21310610765 is an apocalyptic number.

It is an amenable number.

21310610765 is a deficient number, since it is larger than the sum of its proper divisors (4263399595).

21310610765 is a wasteful number, since it uses less digits than its factorization.

21310610765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212911.

The product of its (nonzero) digits is 7560, while the sum is 32.

The spelling of 21310610765 in words is "twenty-one billion, three hundred ten million, six hundred ten thousand, seven hundred sixty-five".