19930978 has 16 divisors (see below), whose sum is σ = 30651264. Its totient is φ = 9717120.

The previous prime is 19930921. The next prime is 19930991. The reversal of 19930978 is 87903991.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13051 + ... + 14497.

It is an arithmetic number, because the mean of its divisors is an integer number (1915704).

Almost surely, 2^19930978 is an apocalyptic number.

19930978 is a deficient number, since it is larger than the sum of its proper divisors (10720286).

19930978 is a wasteful number, since it uses less digits than its factorization.

19930978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1617.

The product of its (nonzero) digits is 122472, while the sum is 46.

The square root of 19930978 is about 4464.4123913456. The cubic root of 19930978 is about 271.1291442040.

The spelling of 19930978 in words is "nineteen million, nine hundred thirty thousand, nine hundred seventy-eight".