20553210111 has 8 divisors (see below), whose sum is σ = 31319177344. Its totient is φ = 11744691480.

The previous prime is 20553210109. The next prime is 20553210173. The reversal of 20553210111 is 11101235502.

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

It is not a de Polignac number, because 20553210111 - 2¹ = 20553210109 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 978724291 = 20553210111 / (2 + 0 + 5 + 5 + 3 + 2 + 1 + 0 + 1 + 1 + 1).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20553210611) 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, 489362125 + ... + 489362166.

It is an arithmetic number, because the mean of its divisors is an integer number (3914897168).

Almost surely, 2^20553210111 is an apocalyptic number.

20553210111 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

20553210111 is a deficient number, since it is larger than the sum of its proper divisors (10765967233).

20553210111 is an equidigital number, since it uses as much as digits as its factorization.

20553210111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 978724301.

The product of its (nonzero) digits is 300, while the sum is 21.

Adding to 20553210111 its reverse (11101235502), we get a palindrome (31654445613).

The spelling of 20553210111 in words is "twenty billion, five hundred fifty-three million, two hundred ten thousand, one hundred eleven".