19798728440279 has 4 divisors (see below), whose sum is σ = 19812042986784. Its totient is φ = 19785413893776.

The previous prime is 19798728440237. The next prime is 19798728440321. The reversal of 19798728440279 is 97204482789791.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (19798728440237) and next prime (19798728440321).

It is a cyclic number.

It is not a de Polignac number, because 19798728440279 - 2¹² = 19798728436183 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19798728440479) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6657271022 + ... + 6657273995.

It is an arithmetic number, because the mean of its divisors is an integer number (4953010746696).

Almost surely, 2^{19798728440279} is an apocalyptic number.

19798728440279 is a deficient number, since it is larger than the sum of its proper divisors (13314546505).

19798728440279 is a wasteful number, since it uses less digits than its factorization.

19798728440279 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13314546504.

The product of its (nonzero) digits is 1024192512, while the sum is 77.

The spelling of 19798728440279 in words is "nineteen trillion, seven hundred ninety-eight billion, seven hundred twenty-eight million, four hundred forty thousand, two hundred seventy-nine".