81964628899 has 2 divisors, whose sum is σ = 81964628900. Its totient is φ = 81964628898.

The previous prime is 81964628839. The next prime is 81964628929. The reversal of 81964628899 is 99882646918.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81964628899 - 2¹³ = 81964620707 is a prime.

It is not a weakly prime, because it can be changed into another prime (81964628839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40982314449 + 40982314450.

It is an arithmetic number, because the mean of its divisors is an integer number (40982314450).

Almost surely, 2^81964628899 is an apocalyptic number.

81964628899 is a deficient number, since it is larger than the sum of its proper divisors (1).

81964628899 is an equidigital number, since it uses as much as digits as its factorization.

81964628899 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 107495424, while the sum is 70.

The spelling of 81964628899 in words is "eighty-one billion, nine hundred sixty-four million, six hundred twenty-eight thousand, eight hundred ninety-nine".