21686553710 has 16 divisors (see below), whose sum is σ = 41332020336. Its totient is φ = 8164349568.

The previous prime is 21686553703. The next prime is 21686553751. The reversal of 21686553710 is 1735568612.

It is a super-2 number, since 2×21686553710² (a number of 21 digits) contains 22 as substring.

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 7 ways as a sum of consecutive naturals, for example, 63783812 + ... + 63784151.

It is an arithmetic number, because the mean of its divisors is an integer number (2583251271).

Almost surely, 2^21686553710 is an apocalyptic number.

21686553710 is a deficient number, since it is larger than the sum of its proper divisors (19645466626).

21686553710 is a wasteful number, since it uses less digits than its factorization.

21686553710 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127567987.

The product of its (nonzero) digits is 302400, while the sum is 44.

The spelling of 21686553710 in words is "twenty-one billion, six hundred eighty-six million, five hundred fifty-three thousand, seven hundred ten".