19508871428 has 6 divisors (see below), whose sum is σ = 34140525006. Its totient is φ = 9754435712.

The previous prime is 19508871409. The next prime is 19508871451. The reversal of 19508871428 is 82417880591.

It can be written as a sum of positive squares in only one way, i.e., 10825986304 + 8682885124 = 104048^2 + 93182^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 19508871428.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2438608925 + ... + 2438608932.

It is an arithmetic number, because the mean of its divisors is an integer number (5690087501).

Almost surely, 2^19508871428 is an apocalyptic number.

It is an amenable number.

19508871428 is a deficient number, since it is larger than the sum of its proper divisors (14631653578).

19508871428 is a wasteful number, since it uses less digits than its factorization.

19508871428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4877217861 (or 4877217859 counting only the distinct ones).

The product of its (nonzero) digits is 1290240, while the sum is 53.

The spelling of 19508871428 in words is "nineteen billion, five hundred eight million, eight hundred seventy-one thousand, four hundred twenty-eight".