21680250130765 has 8 divisors (see below), whose sum is σ = 26016325330968. Its totient is φ = 17344183321920.

The previous prime is 21680250130739. The next prime is 21680250130793. The reversal of 21680250130765 is 56703105208612.

It can be written as a sum of positive squares in 4 ways, for example, as 364050529956 + 21316199600809 = 603366^2 + 4616947^2 .

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

It is a de Polignac number, because none of the positive numbers 2^k-21680250130765 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8039439 + ... + 10391971.

It is an arithmetic number, because the mean of its divisors is an integer number (3252040666371).

Almost surely, 2^{21680250130765} is an apocalyptic number.

It is an amenable number.

21680250130765 is a deficient number, since it is larger than the sum of its proper divisors (4336075200203).

21680250130765 is a wasteful number, since it uses less digits than its factorization.

21680250130765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4195679.

The product of its (nonzero) digits is 604800, while the sum is 46.

The spelling of 21680250130765 in words is "twenty-one trillion, six hundred eighty billion, two hundred fifty million, one hundred thirty thousand, seven hundred sixty-five".