20815361839 has 8 divisors (see below), whose sum is σ = 21670790480. Its totient is φ = 19975346496.

The previous prime is 20815361803. The next prime is 20815361851. The reversal of 20815361839 is 93816351802.

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

It is a cyclic number.

It is not a de Polignac number, because 20815361839 - 2²¹ = 20813264687 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20815361899) 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 7 ways as a sum of consecutive naturals, for example, 3850569 + ... + 3855970.

It is an arithmetic number, because the mean of its divisors is an integer number (2708848810).

Almost surely, 2^20815361839 is an apocalyptic number.

20815361839 is a deficient number, since it is larger than the sum of its proper divisors (855428641).

20815361839 is an equidigital number, since it uses as much as digits as its factorization.

20815361839 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7706649.

The product of its (nonzero) digits is 311040, while the sum is 46.

The spelling of 20815361839 in words is "twenty billion, eight hundred fifteen million, three hundred sixty-one thousand, eight hundred thirty-nine".