21585316710870 has 192 divisors, whose sum is σ = 61335166464000. Its totient is φ = 5223292542720.

The previous prime is 21585316710869. The next prime is 21585316710889. The reversal of 21585316710870 is 7801761358512.

21585316710870 is a `hidden beast` number, since 2 + 15 + 8 + 531 + 6 + 7 + 10 + 87 + 0 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2346480531 + ... + 2346489729.

It is an arithmetic number, because the mean of its divisors is an integer number (319453992000).

Almost surely, 2^{21585316710870} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21585316710870, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30667583232000).

21585316710870 is an abundant number, since it is smaller than the sum of its proper divisors (39749849753130).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21585316710870 is a wasteful number, since it uses less digits than its factorization.

21585316710870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13275 (or 13272 counting only the distinct ones).

The product of its (nonzero) digits is 2822400, while the sum is 54.

The spelling of 21585316710870 in words is "twenty-one trillion, five hundred eighty-five billion, three hundred sixteen million, seven hundred ten thousand, eight hundred seventy".