21101211021021 has 8 divisors (see below), whose sum is σ = 28383929869440. Its totient is φ = 13942983093312.

The previous prime is 21101211021019. The next prime is 21101211021031. The reversal of 21101211021021 is 12012011210112.

It is a happy number.

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

It is not a de Polignac number, because 21101211021021 - 2¹ = 21101211021019 is a prime.

It is a super-2 number, since 2×21101211021021² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101211021031) 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, 31122729781 + ... + 31122730458.

It is an arithmetic number, because the mean of its divisors is an integer number (3547991233680).

Almost surely, 2^{21101211021021} is an apocalyptic number.

It is an amenable number.

21101211021021 is a deficient number, since it is larger than the sum of its proper divisors (7282718848419).

21101211021021 is a wasteful number, since it uses less digits than its factorization.

21101211021021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62245460355.

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

Adding to 21101211021021 its reverse (12012011210112), we get a palindrome (33113222231133).

The spelling of 21101211021021 in words is "twenty-one trillion, one hundred one billion, two hundred eleven million, twenty-one thousand, twenty-one".