21019845686 has 16 divisors (see below), whose sum is σ = 36713909664. Its totient is φ = 8838533184.

The previous prime is 21019845661. The next prime is 21019845727. The reversal of 21019845686 is 68654891012.

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, 14163575 + ... + 14165058.

It is an arithmetic number, because the mean of its divisors is an integer number (2294619354).

Almost surely, 2^21019845686 is an apocalyptic number.

21019845686 is a deficient number, since it is larger than the sum of its proper divisors (15694063978).

21019845686 is a wasteful number, since it uses less digits than its factorization.

21019845686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28328695.

The product of its (nonzero) digits is 829440, while the sum is 50.

The spelling of 21019845686 in words is "twenty-one billion, nineteen million, eight hundred forty-five thousand, six hundred eighty-six".