20859145019 has 4 divisors (see below), whose sum is σ = 20911687344. Its totient is φ = 20806602696.

The previous prime is 20859145001. The next prime is 20859145031. The reversal of 20859145019 is 91054195802.

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

It is a cyclic number.

It is not a de Polignac number, because 20859145019 - 2⁸ = 20859144763 is a prime.

It is a super-2 number, since 2×20859145019² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20859145039) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26270567 + ... + 26271360.

It is an arithmetic number, because the mean of its divisors is an integer number (5227921836).

Almost surely, 2^20859145019 is an apocalyptic number.

20859145019 is a deficient number, since it is larger than the sum of its proper divisors (52542325).

20859145019 is an equidigital number, since it uses as much as digits as its factorization.

20859145019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52542324.

The product of its (nonzero) digits is 129600, while the sum is 44.

The spelling of 20859145019 in words is "twenty billion, eight hundred fifty-nine million, one hundred forty-five thousand, nineteen".