81923432918 has 8 divisors (see below), whose sum is σ = 122888734248. Its totient is φ = 40960521504.

The previous prime is 81923432909. The next prime is 81923432923.

81923432918 is nontrivially palindromic in base 10.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×81923432918² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 509171 + ... + 650462.

It is an arithmetic number, because the mean of its divisors is an integer number (15361091781).

Almost surely, 2^81923432918 is an apocalyptic number.

81923432918 is a deficient number, since it is larger than the sum of its proper divisors (40965301330).

81923432918 is a wasteful number, since it uses less digits than its factorization.

81923432918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1194958.

The product of its digits is 746496, while the sum is 50.

The spelling of 81923432918 in words is "eighty-one billion, nine hundred twenty-three million, four hundred thirty-two thousand, nine hundred eighteen".