20585981690 has 8 divisors (see below), whose sum is σ = 37054767060. Its totient is φ = 8234392672.

The previous prime is 20585981687. The next prime is 20585981707. The reversal of 20585981690 is 9618958502.

It can be written as a sum of positive squares in 2 ways, for example, as 20189852281 + 396129409 = 142091^2 + 19903^2 .

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

It is a super-2 number, since 2×20585981690² (a number of 21 digits) contains 22 as substring.

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 3 ways as a sum of consecutive naturals, for example, 1029299075 + ... + 1029299094.

Almost surely, 2^20585981690 is an apocalyptic number.

20585981690 is a deficient number, since it is larger than the sum of its proper divisors (16468785370).

20585981690 is a wasteful number, since it uses less digits than its factorization.

20585981690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2058598176.

The product of its (nonzero) digits is 1555200, while the sum is 53.

The spelling of 20585981690 in words is "twenty billion, five hundred eighty-five million, nine hundred eighty-one thousand, six hundred ninety".