81384402377 has 4 divisors (see below), whose sum is σ = 81550155216. Its totient is φ = 81218649540.

The previous prime is 81384402349. The next prime is 81384402389. The reversal of 81384402377 is 77320448318.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81384402377 - 2¹⁰ = 81384401353 is a prime.

It is a super-2 number, since 2×81384402377² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81384402347) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 82875683 + ... + 82876664.

It is an arithmetic number, because the mean of its divisors is an integer number (20387538804).

Almost surely, 2^81384402377 is an apocalyptic number.

It is an amenable number.

81384402377 is a deficient number, since it is larger than the sum of its proper divisors (165752839).

81384402377 is a wasteful number, since it uses less digits than its factorization.

81384402377 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165752838.

The product of its (nonzero) digits is 903168, while the sum is 47.

The spelling of 81384402377 in words is "eighty-one billion, three hundred eighty-four million, four hundred two thousand, three hundred seventy-seven".