27728921786 has 8 divisors (see below), whose sum is σ = 41611036500. Its totient is φ = 13858576288.

The previous prime is 27728921783. The next prime is 27728921789. The reversal of 27728921786 is 68712982772.

It is an interprime number because it is at equal distance from previous prime (27728921783) and next prime (27728921789).

It can be written as a sum of positive squares in 2 ways, for example, as 27570942025 + 157979761 = 166045^2 + 12569^2 .

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

It is not an unprimeable number, because it can be changed into a prime (27728921783) 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, 2936411 + ... + 2945838.

Almost surely, 2^27728921786 is an apocalyptic number.

27728921786 is a deficient number, since it is larger than the sum of its proper divisors (13882114714).

27728921786 is a wasteful number, since it uses less digits than its factorization.

27728921786 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5884608.

The product of its digits is 9483264, while the sum is 59.

The spelling of 27728921786 in words is "twenty-seven billion, seven hundred twenty-eight million, nine hundred twenty-one thousand, seven hundred eighty-six".