19781879315 has 16 divisors (see below), whose sum is σ = 26498520576. Its totient is φ = 14052242400.

The previous prime is 19781879311. The next prime is 19781879321. The reversal of 19781879315 is 51397818791.

It is not a de Polignac number, because 19781879315 - 2² = 19781879311 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19781879311) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4179851 + ... + 4184580.

It is an arithmetic number, because the mean of its divisors is an integer number (1656157536).

Almost surely, 2^19781879315 is an apocalyptic number.

19781879315 is a deficient number, since it is larger than the sum of its proper divisors (6716641261).

19781879315 is a wasteful number, since it uses less digits than its factorization.

19781879315 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8364490.

The product of its digits is 3810240, while the sum is 59.

The spelling of 19781879315 in words is "nineteen billion, seven hundred eighty-one million, eight hundred seventy-nine thousand, three hundred fifteen".