18416973 has 4 divisors (see below), whose sum is σ = 24555968. Its totient is φ = 12277980.

The previous prime is 18416971. The next prime is 18416977. The reversal of 18416973 is 37961481.

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, and also an emirpimes, since its reverse is a distinct semiprime: 37961481 = 3 ⋅12653827.

It is not a de Polignac number, because 18416973 - 2¹ = 18416971 is a prime.

It is the 4292-nd Hogben number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18416971) by changing a digit.

It is a nontrivial repunit in base 4291.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3069493 + ... + 3069498.

It is an arithmetic number, because the mean of its divisors is an integer number (6138992).

Almost surely, 2^18416973 is an apocalyptic number.

It is an amenable number.

18416973 is a deficient number, since it is larger than the sum of its proper divisors (6138995).

18416973 is an equidigital number, since it uses as much as digits as its factorization.

18416973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6138994.

The product of its digits is 36288, while the sum is 39.

The square root of 18416973 is about 4291.5000873820. The cubic root of 18416973 is about 264.0823750058.

The spelling of 18416973 in words is "eighteen million, four hundred sixteen thousand, nine hundred seventy-three".