21540486986 has 8 divisors (see below), whose sum is σ = 32449403844. Its totient is φ = 10724019040.

The previous prime is 21540486959. The next prime is 21540486997. The reversal of 21540486986 is 68968404512.

It can be written as a sum of positive squares in 2 ways, for example, as 18787910761 + 2752576225 = 137069^2 + 52465^2 .

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

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23111645 + ... + 23112576.

Almost surely, 2^21540486986 is an apocalyptic number.

21540486986 is a deficient number, since it is larger than the sum of its proper divisors (10908916858).

21540486986 is a wasteful number, since it uses less digits than its factorization.

21540486986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46224456.

The product of its (nonzero) digits is 3317760, while the sum is 53.

The spelling of 21540486986 in words is "twenty-one billion, five hundred forty million, four hundred eighty-six thousand, nine hundred eighty-six".