21552426641 has 2 divisors, whose sum is σ = 21552426642. Its totient is φ = 21552426640.

The previous prime is 21552426613. The next prime is 21552426677. The reversal of 21552426641 is 14662425512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17062890625 + 4489536016 = 130625^2 + 67004^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21552426641 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21552426595 and 21552426604.

It is not a weakly prime, because it can be changed into another prime (21552426241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10776213320 + 10776213321.

It is an arithmetic number, because the mean of its divisors is an integer number (10776213321).

Almost surely, 2^21552426641 is an apocalyptic number.

It is an amenable number.

21552426641 is a deficient number, since it is larger than the sum of its proper divisors (1).

21552426641 is an equidigital number, since it uses as much as digits as its factorization.

21552426641 is an evil number, because the sum of its binary digits is even.

The product of its digits is 115200, while the sum is 38.

The spelling of 21552426641 in words is "twenty-one billion, five hundred fifty-two million, four hundred twenty-six thousand, six hundred forty-one".