20511155105 has 8 divisors (see below), whose sum is σ = 28129584192. Its totient is φ = 14064792048.

The previous prime is 20511155099. The next prime is 20511155107. The reversal of 20511155105 is 50155111502.

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 20511155105 - 2⁴ = 20511155089 is a prime.

It is a super-2 number, since 2×20511155105² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20511155107) by changing a digit.

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, 293016467 + ... + 293016536.

It is an arithmetic number, because the mean of its divisors is an integer number (3516198024).

Almost surely, 2^20511155105 is an apocalyptic number.

It is an amenable number.

20511155105 is a deficient number, since it is larger than the sum of its proper divisors (7618429087).

20511155105 is an equidigital number, since it uses as much as digits as its factorization.

20511155105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 586033015.

The product of its (nonzero) digits is 1250, while the sum is 26.

Adding to 20511155105 its reverse (50155111502), we get a palindrome (70666266607).

It can be divided in two parts, 20511 and 155105, that added together give a cube (175616 = 56³).

The spelling of 20511155105 in words is "twenty billion, five hundred eleven million, one hundred fifty-five thousand, one hundred five".