81563229053 has 2 divisors, whose sum is σ = 81563229054. Its totient is φ = 81563229052.

The previous prime is 81563228969. The next prime is 81563229067. The reversal of 81563229053 is 35092236518.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 77929188964 + 3634040089 = 279158^2 + 60283^2 .

It is a cyclic number.

It is not a de Polignac number, because 81563229053 - 2¹⁰ = 81563228029 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81563228995 and 81563229013.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81563226053) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40781614526 + 40781614527.

It is an arithmetic number, because the mean of its divisors is an integer number (40781614527).

Almost surely, 2^81563229053 is an apocalyptic number.

It is an amenable number.

81563229053 is a deficient number, since it is larger than the sum of its proper divisors (1).

81563229053 is an equidigital number, since it uses as much as digits as its factorization.

81563229053 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 388800, while the sum is 44.

The spelling of 81563229053 in words is "eighty-one billion, five hundred sixty-three million, two hundred twenty-nine thousand, fifty-three".