21222040632561 has 48 divisors (see below), whose sum is σ = 32081329463040. Its totient is φ = 13492966164480.

The previous prime is 21222040632503. The next prime is 21222040632581. The reversal of 21222040632561 is 16523604022212.

21222040632561 is a `hidden beast` number, since 2 + 1 + 2 + 2 + 20 + 40 + 6 + 32 + 561 = 666.

It is not a de Polignac number, because 21222040632561 - 2¹⁴ = 21222040616177 is a prime.

It is a super-2 number, since 2×21222040632561² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21222040632581) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 124691041 + ... + 124861121.

It is an arithmetic number, because the mean of its divisors is an integer number (668361030480).

Almost surely, 2^{21222040632561} is an apocalyptic number.

It is an amenable number.

21222040632561 is a deficient number, since it is larger than the sum of its proper divisors (10859288830479).

21222040632561 is a wasteful number, since it uses less digits than its factorization.

21222040632561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171886 (or 171883 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

Adding to 21222040632561 its reverse (16523604022212), we get a palindrome (37745644654773).

The spelling of 21222040632561 in words is "twenty-one trillion, two hundred twenty-two billion, forty million, six hundred thirty-two thousand, five hundred sixty-one".