19408402138 has 16 divisors (see below), whose sum is σ = 30827701224. Its totient is φ = 9132597760.

The previous prime is 19408402103. The next prime is 19408402177. The reversal of 19408402138 is 83120480491.

It can be written as a sum of positive squares in 4 ways, for example, as 8052729169 + 11355672969 = 89737^2 + 106563^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 19408402138.

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 7 ways as a sum of consecutive naturals, for example, 725928 + ... + 752188.

Almost surely, 2^19408402138 is an apocalyptic number.

19408402138 is a deficient number, since it is larger than the sum of its proper divisors (11419299086).

19408402138 is a wasteful number, since it uses less digits than its factorization.

19408402138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48017.

The product of its (nonzero) digits is 55296, while the sum is 40.

The spelling of 19408402138 in words is "nineteen billion, four hundred eight million, four hundred two thousand, one hundred thirty-eight".