1989278692 has 12 divisors (see below), whose sum is σ = 3540242160. Its totient is φ = 977780936.

The previous prime is 1989278677. The next prime is 1989278719. The reversal of 1989278692 is 2968729891.

It is a self number, because there is not a number n which added to its sum of digits gives 1989278692.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4214338 + ... + 4214809.

It is an arithmetic number, because the mean of its divisors is an integer number (295020180).

Almost surely, 2^1989278692 is an apocalyptic number.

It is an amenable number.

1989278692 is a deficient number, since it is larger than the sum of its proper divisors (1550963468).

1989278692 is a wasteful number, since it uses less digits than its factorization.

1989278692 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8429210 (or 8429208 counting only the distinct ones).

The product of its digits is 7838208, while the sum is 61.

The square root of 1989278692 is about 44601.3306079538. The cubic root of 1989278692 is about 1257.6656813924.

The spelling of 1989278692 in words is "one billion, nine hundred eighty-nine million, two hundred seventy-eight thousand, six hundred ninety-two".