19917478427 has 8 divisors (see below), whose sum is σ = 24832180992. Its totient is φ = 15520113000.

The previous prime is 19917478411. The next prime is 19917478463. The reversal of 19917478427 is 72487471991.

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

It is not a de Polignac number, because 19917478427 - 2⁴ = 19917478411 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19917478127) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 129334199 + ... + 129334352.

It is an arithmetic number, because the mean of its divisors is an integer number (3104022624).

Almost surely, 2^19917478427 is an apocalyptic number.

19917478427 is a deficient number, since it is larger than the sum of its proper divisors (4914702565).

19917478427 is a wasteful number, since it uses less digits than its factorization.

19917478427 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 258668569.

The product of its digits is 7112448, while the sum is 59.

The spelling of 19917478427 in words is "nineteen billion, nine hundred seventeen million, four hundred seventy-eight thousand, four hundred twenty-seven".