20011221112104 has 24 divisors (see below), whose sum is σ = 54197057178810. Its totient is φ = 6670407037344.

The previous prime is 20011221112081. The next prime is 20011221112109. The reversal of 20011221112104 is 40121112211002.

It can be written as a sum of positive squares in only one way, i.e., 14345383500900 + 5665837611204 = 3787530^2 + 2380302^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (20011221112109) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 138966813207 + ... + 138966813350.

Almost surely, 2^{20011221112104} is an apocalyptic number.

20011221112104 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

20011221112104 is an abundant number, since it is smaller than the sum of its proper divisors (34185836066706).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20011221112104 is a wasteful number, since it uses less digits than its factorization.

20011221112104 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 277933626569 (or 277933626562 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 20011221112104 its reverse (40121112211002), we get a palindrome (60132333323106).

The spelling of 20011221112104 in words is "twenty trillion, eleven billion, two hundred twenty-one million, one hundred twelve thousand, one hundred four".