81353887201 has 2 divisors, whose sum is σ = 81353887202. Its totient is φ = 81353887200.

The previous prime is 81353887193. The next prime is 81353887217. The reversal of 81353887201 is 10278835318.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71974158400 + 9379728801 = 268280^2 + 96849^2 .

It is a cyclic number.

It is not a de Polignac number, because 81353887201 - 2³ = 81353887193 is a prime.

It is a super-2 number, since 2×81353887201² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (81323887201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40676943600 + 40676943601.

It is an arithmetic number, because the mean of its divisors is an integer number (40676943601).

Almost surely, 2^81353887201 is an apocalyptic number.

It is an amenable number.

81353887201 is a deficient number, since it is larger than the sum of its proper divisors (1).

81353887201 is an equidigital number, since it uses as much as digits as its factorization.

81353887201 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 322560, while the sum is 46.

The spelling of 81353887201 in words is "eighty-one billion, three hundred fifty-three million, eight hundred eighty-seven thousand, two hundred one".