18549497973 has 8 divisors (see below), whose sum is σ = 26034383200. Its totient is φ = 11715472368.

The previous prime is 18549497959. The next prime is 18549497983. The reversal of 18549497973 is 37979494581.

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

It is not a de Polignac number, because 18549497973 - 2⁴ = 18549497957 is a prime.

It is a super-2 number, since 2×18549497973² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18549497933) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 162714838 + ... + 162714951.

It is an arithmetic number, because the mean of its divisors is an integer number (3254297900).

Almost surely, 2^18549497973 is an apocalyptic number.

It is an amenable number.

18549497973 is a deficient number, since it is larger than the sum of its proper divisors (7484885227).

18549497973 is a wasteful number, since it uses less digits than its factorization.

18549497973 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 325429811.

The product of its digits is 68584320, while the sum is 66.

The spelling of 18549497973 in words is "eighteen billion, five hundred forty-nine million, four hundred ninety-seven thousand, nine hundred seventy-three".