19901027042 has 16 divisors (see below), whose sum is σ = 32257544760. Its totient is φ = 9153737472.

The previous prime is 19901026973. The next prime is 19901027171. The reversal of 19901027042 is 24072010991.

It is a Cunningham number, because it is equal to 141071²+1.

It can be written as a sum of positive squares in 4 ways, for example, as 18829053961 + 1071973081 = 137219^2 + 32741^2 .

It is a junction number, because it is equal to n+sod(n) for n = 19901026993 and 19901027011.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1298567 + ... + 1313802.

Almost surely, 2^19901027042 is an apocalyptic number.

19901027042 is a deficient number, since it is larger than the sum of its proper divisors (12356517718).

19901027042 is a wasteful number, since it uses less digits than its factorization.

19901027042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2612677.

The product of its (nonzero) digits is 9072, while the sum is 35.

The spelling of 19901027042 in words is "nineteen billion, nine hundred one million, twenty-seven thousand, forty-two".