21011140021 has 16 divisors (see below), whose sum is σ = 23220691200. Its totient is φ = 18910236928.

The previous prime is 21011139973. The next prime is 21011140037. The reversal of 21011140021 is 12004111012.

It is a cyclic number.

It is not a de Polignac number, because 21011140021 - 2⁷ = 21011139893 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21011139983 and 21011140010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011140421) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2775840 + ... + 2783398.

It is an arithmetic number, because the mean of its divisors is an integer number (1451293200).

Almost surely, 2^21011140021 is an apocalyptic number.

It is an amenable number.

21011140021 is a deficient number, since it is larger than the sum of its proper divisors (2209551179).

21011140021 is a wasteful number, since it uses less digits than its factorization.

21011140021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14708.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21011140021 its reverse (12004111012), we get a palindrome (33015251033).

The spelling of 21011140021 in words is "twenty-one billion, eleven million, one hundred forty thousand, twenty-one".