1986389842 has 4 divisors (see below), whose sum is σ = 2979584766. Its totient is φ = 993194920.

The previous prime is 1986389813. The next prime is 1986389869. The reversal of 1986389842 is 2489836891.

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., 1110289041 + 876100801 = 33321^2 + 29599^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 496597459 + ... + 496597462.

Almost surely, 2^1986389842 is an apocalyptic number.

1986389842 is a deficient number, since it is larger than the sum of its proper divisors (993194924).

1986389842 is an equidigital number, since it uses as much as digits as its factorization.

1986389842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 993194923.

The product of its digits is 5971968, while the sum is 58.

The square root of 1986389842 is about 44568.9335972940. The cubic root of 1986389842 is about 1257.0565883134.

The spelling of 1986389842 in words is "one billion, nine hundred eighty-six million, three hundred eighty-nine thousand, eight hundred forty-two".