1986947866 has 4 divisors (see below), whose sum is σ = 2980421802. Its totient is φ = 993473932.

The previous prime is 1986947849. The next prime is 1986947891. The reversal of 1986947866 is 6687496891.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1405125225 + 581822641 = 37485^2 + 24121^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1986947798 and 1986947807.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 496736965 + ... + 496736968.

Almost surely, 2^1986947866 is an apocalyptic number.

1986947866 is a deficient number, since it is larger than the sum of its proper divisors (993473936).

1986947866 is an equidigital number, since it uses as much as digits as its factorization.

1986947866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 993473935.

The product of its digits is 31352832, while the sum is 64.

The square root of 1986947866 is about 44575.1933927381. The cubic root of 1986947866 is about 1257.1742896251.

The spelling of 1986947866 in words is "one billion, nine hundred eighty-six million, nine hundred forty-seven thousand, eight hundred sixty-six".