20131307778 has 16 divisors (see below), whose sum is σ = 40271147136. Its totient is φ = 6709014000.

The previous prime is 20131307761. The next prime is 20131307969. The reversal of 20131307778 is 87770313102.

It is a Curzon number.

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, 324601 + ... + 381612.

It is an arithmetic number, because the mean of its divisors is an integer number (2516946696).

Almost surely, 2^20131307778 is an apocalyptic number.

20131307778 is an abundant number, since it is smaller than the sum of its proper divisors (20139839358).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20131307778 is a wasteful number, since it uses less digits than its factorization.

20131307778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 710969.

The product of its (nonzero) digits is 49392, while the sum is 39.

The spelling of 20131307778 in words is "twenty billion, one hundred thirty-one million, three hundred seven thousand, seven hundred seventy-eight".