21101012112021 has 4 divisors (see below), whose sum is σ = 28134682816032. Its totient is φ = 14067341408012.

The previous prime is 21101012112007. The next prime is 21101012112043. The reversal of 21101012112021 is 12021121010112.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21101012112021 - 2⁵ = 21101012111989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101012112121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3516835352001 + ... + 3516835352006.

It is an arithmetic number, because the mean of its divisors is an integer number (7033670704008).

Almost surely, 2^{21101012112021} is an apocalyptic number.

It is an amenable number.

21101012112021 is a deficient number, since it is larger than the sum of its proper divisors (7033670704011).

21101012112021 is an equidigital number, since it uses as much as digits as its factorization.

21101012112021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7033670704010.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21101012112021 its reverse (12021121010112), we get a palindrome (33122133122133).

The spelling of 21101012112021 in words is "twenty-one trillion, one hundred one billion, twelve million, one hundred twelve thousand, twenty-one".