20315530778 has 16 divisors (see below), whose sum is σ = 32081521920. Its totient is φ = 9621835776.

The previous prime is 20315530771. The next prime is 20315530783. The reversal of 20315530778 is 87703551302.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20315530771) 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, 282650 + ... + 347162.

It is an arithmetic number, because the mean of its divisors is an integer number (2005095120).

Almost surely, 2^20315530778 is an apocalyptic number.

20315530778 is a deficient number, since it is larger than the sum of its proper divisors (11765991142).

20315530778 is a wasteful number, since it uses less digits than its factorization.

20315530778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72821.

The product of its (nonzero) digits is 176400, while the sum is 41.

The spelling of 20315530778 in words is "twenty billion, three hundred fifteen million, five hundred thirty thousand, seven hundred seventy-eight".