21001021106 has 16 divisors (see below), whose sum is σ = 33928206144. Its totient is φ = 9691784784.

The previous prime is 21001021103. The next prime is 21001021123. The reversal of 21001021106 is 60112010012.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21001021103) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 257681 + ... + 329243.

It is an arithmetic number, because the mean of its divisors is an integer number (2120512884).

Almost surely, 2^21001021106 is an apocalyptic number.

21001021106 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21001021106 is a deficient number, since it is larger than the sum of its proper divisors (12927185038).

21001021106 is a wasteful number, since it uses less digits than its factorization.

21001021106 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82865.

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 21001021106 its reverse (60112010012), we get a palindrome (81113031118).

The spelling of 21001021106 in words is "twenty-one billion, one million, twenty-one thousand, one hundred six".