27991874211808 has 24 divisors (see below), whose sum is σ = 59348156382648. Its totient is φ = 12919326559104.

The previous prime is 27991874211803. The next prime is 27991874211811. The reversal of 27991874211808 is 80811247819972.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27991874211803) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33644079166 + ... + 33644079997.

It is an arithmetic number, because the mean of its divisors is an integer number (2472839849277).

Almost surely, 2^{27991874211808} is an apocalyptic number.

It is an amenable number.

27991874211808 is an abundant number, since it is smaller than the sum of its proper divisors (31356282170840).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

27991874211808 is a wasteful number, since it uses less digits than its factorization.

27991874211808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67288159186 (or 67288159178 counting only the distinct ones).

The product of its (nonzero) digits is 32514048, while the sum is 67.

The spelling of 27991874211808 in words is "twenty-seven trillion, nine hundred ninety-one billion, eight hundred seventy-four million, two hundred eleven thousand, eight hundred eight".