21728666483 has 2 divisors, whose sum is σ = 21728666484. Its totient is φ = 21728666482.

The previous prime is 21728666471. The next prime is 21728666489. The reversal of 21728666483 is 38466682712.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21728666483 - 2¹⁰ = 21728665459 is a prime.

It is not a weakly prime, because it can be changed into another prime (21728666489) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10864333241 + 10864333242.

It is an arithmetic number, because the mean of its divisors is an integer number (10864333242).

Almost surely, 2^21728666483 is an apocalyptic number.

21728666483 is a deficient number, since it is larger than the sum of its proper divisors (1).

21728666483 is an equidigital number, since it uses as much as digits as its factorization.

21728666483 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4644864, while the sum is 53.

The spelling of 21728666483 in words is "twenty-one billion, seven hundred twenty-eight million, six hundred sixty-six thousand, four hundred eighty-three".