21506202111041 has 4 divisors (see below), whose sum is σ = 21557529562800. Its totient is φ = 21454874659284.

The previous prime is 21506202111019. The next prime is 21506202111067. The reversal of 21506202111041 is 14011120260512.

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 21506202111041 - 2³⁰ = 21505128369217 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21506202111041.

It is not an unprimeable number, because it can be changed into a prime (21506202111001) 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, 25663725251 + ... + 25663726088.

It is an arithmetic number, because the mean of its divisors is an integer number (5389382390700).

Almost surely, 2^{21506202111041} is an apocalyptic number.

It is an amenable number.

21506202111041 is a deficient number, since it is larger than the sum of its proper divisors (51327451759).

21506202111041 is an equidigital number, since it uses as much as digits as its factorization.

21506202111041 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51327451758.

The product of its (nonzero) digits is 960, while the sum is 26.

Adding to 21506202111041 its reverse (14011120260512), we get a palindrome (35517322371553).

The spelling of 21506202111041 in words is "twenty-one trillion, five hundred six billion, two hundred two million, one hundred eleven thousand, forty-one".