27986755621 has 12 divisors (see below), whose sum is σ = 30946529376. Its totient is φ = 25290136520.

The previous prime is 27986755619. The next prime is 27986755729. The reversal of 27986755621 is 12655768972.

It is not a de Polignac number, because 27986755621 - 2¹ = 27986755619 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27986756621) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 672295 + ... + 712708.

It is an arithmetic number, because the mean of its divisors is an integer number (2578877448).

Almost surely, 2^27986755621 is an apocalyptic number.

It is an amenable number.

27986755621 is a deficient number, since it is larger than the sum of its proper divisors (2959773755).

27986755621 is a wasteful number, since it uses less digits than its factorization.

27986755621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1385192 (or 1385181 counting only the distinct ones).

The product of its digits is 12700800, while the sum is 58.

The spelling of 27986755621 in words is "twenty-seven billion, nine hundred eighty-six million, seven hundred fifty-five thousand, six hundred twenty-one".