21626640841 has 12 divisors (see below), whose sum is σ = 23633062860. Its totient is φ = 19779888960.

The previous prime is 21626640839. The next prime is 21626640863. The reversal of 21626640841 is 14804662612.

It can be written as a sum of positive squares in 6 ways, for example, as 7221600400 + 14405040441 = 84980^2 + 120021^2 .

It is not a de Polignac number, because 21626640841 - 2¹ = 21626640839 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21626640794 and 21626640803.

It is not an unprimeable number, because it can be changed into a prime (21626640821) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 568590 + ... + 605431.

It is an arithmetic number, because the mean of its divisors is an integer number (1969421905).

Almost surely, 2^21626640841 is an apocalyptic number.

It is an amenable number.

21626640841 is a deficient number, since it is larger than the sum of its proper divisors (2006422019).

21626640841 is a wasteful number, since it uses less digits than its factorization.

21626640841 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1174156 (or 1174143 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 40.

The spelling of 21626640841 in words is "twenty-one billion, six hundred twenty-six million, six hundred forty thousand, eight hundred forty-one".