20315256413 has 4 divisors (see below), whose sum is σ = 20418379740. Its totient is φ = 20212133088.

The previous prime is 20315256347. The next prime is 20315256421. The reversal of 20315256413 is 31465251302.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 20130785689 + 184470724 = 141883^2 + 13582^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20315256413 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20315256413.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20315256473) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 51561368 + ... + 51561761.

It is an arithmetic number, because the mean of its divisors is an integer number (5104594935).

Almost surely, 2^20315256413 is an apocalyptic number.

It is an amenable number.

20315256413 is a deficient number, since it is larger than the sum of its proper divisors (103123327).

20315256413 is a wasteful number, since it uses less digits than its factorization.

20315256413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103123326.

The product of its (nonzero) digits is 21600, while the sum is 32.

The spelling of 20315256413 in words is "twenty billion, three hundred fifteen million, two hundred fifty-six thousand, four hundred thirteen".