81398630667 has 16 divisors (see below), whose sum is σ = 111652849440. Its totient is φ = 52710031872.

The previous prime is 81398630633. The next prime is 81398630717. The reversal of 81398630667 is 76603689318.

It is not a de Polignac number, because 81398630667 - 2²⁴ = 81381853451 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81398630617) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 552492 + ... + 684137.

It is an arithmetic number, because the mean of its divisors is an integer number (6978303090).

Almost surely, 2^81398630667 is an apocalyptic number.

81398630667 is a deficient number, since it is larger than the sum of its proper divisors (30254218773).

81398630667 is a wasteful number, since it uses less digits than its factorization.

81398630667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1237262.

The product of its (nonzero) digits is 7838208, while the sum is 57.

The spelling of 81398630667 in words is "eighty-one billion, three hundred ninety-eight million, six hundred thirty thousand, six hundred sixty-seven".