1985506478 has 8 divisors (see below), whose sum is σ = 3000994920. Its totient is φ = 985174840.

The previous prime is 1985506463. The next prime is 1985506519. The reversal of 1985506478 is 8746055891.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3788873 + ... + 3789396.

It is an arithmetic number, because the mean of its divisors is an integer number (375124365).

Almost surely, 2^1985506478 is an apocalyptic number.

1985506478 is a deficient number, since it is larger than the sum of its proper divisors (1015488442).

1985506478 is a wasteful number, since it uses less digits than its factorization.

1985506478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7578402.

The product of its (nonzero) digits is 2419200, while the sum is 53.

The square root of 1985506478 is about 44559.0224084865. The cubic root of 1985506478 is about 1256.8702195285.

The spelling of 1985506478 in words is "one billion, nine hundred eighty-five million, five hundred six thousand, four hundred seventy-eight".