19974251978 has 8 divisors (see below), whose sum is σ = 29976078240. Its totient is φ = 9982225900.

The previous prime is 19974251867. The next prime is 19974251981. The reversal of 19974251978 is 87915247991.

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

It is a self number, because there is not a number n which added to its sum of digits gives 19974251978.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2444948 + ... + 2453103.

It is an arithmetic number, because the mean of its divisors is an integer number (3747009780).

Almost surely, 2^19974251978 is an apocalyptic number.

19974251978 is a deficient number, since it is larger than the sum of its proper divisors (10001826262).

19974251978 is a wasteful number, since it uses less digits than its factorization.

19974251978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4900092.

The product of its digits is 11430720, while the sum is 62.

The spelling of 19974251978 in words is "nineteen billion, nine hundred seventy-four million, two hundred fifty-one thousand, nine hundred seventy-eight".