21627530641 has 2 divisors, whose sum is σ = 21627530642. Its totient is φ = 21627530640.

The previous prime is 21627530629. The next prime is 21627530723. The reversal of 21627530641 is 14603572612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17360697600 + 4266833041 = 131760^2 + 65321^2 .

It is a cyclic number.

It is not a de Polignac number, because 21627530641 - 2⁷ = 21627530513 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21627530641.

It is not a weakly prime, because it can be changed into another prime (21627530341) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10813765320 + 10813765321.

It is an arithmetic number, because the mean of its divisors is an integer number (10813765321).

Almost surely, 2^21627530641 is an apocalyptic number.

It is an amenable number.

21627530641 is a deficient number, since it is larger than the sum of its proper divisors (1).

21627530641 is an equidigital number, since it uses as much as digits as its factorization.

21627530641 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 60480, while the sum is 37.

The spelling of 21627530641 in words is "twenty-one billion, six hundred twenty-seven million, five hundred thirty thousand, six hundred forty-one".