18451973 has 4 divisors (see below), whose sum is σ = 18466080. Its totient is φ = 18437868.

The previous prime is 18451949. The next prime is 18451981. The reversal of 18451973 is 37915481.

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 18451973 - 2¹⁴ = 18435589 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18451903) 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, 4865 + ... + 7782.

It is an arithmetic number, because the mean of its divisors is an integer number (4616520).

Almost surely, 2^18451973 is an apocalyptic number.

It is an amenable number.

18451973 is a deficient number, since it is larger than the sum of its proper divisors (14107).

18451973 is a wasteful number, since it uses less digits than its factorization.

18451973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14106.

The product of its digits is 30240, while the sum is 38.

The square root of 18451973 is about 4295.5759800055. The cubic root of 18451973 is about 264.2495583639.

The spelling of 18451973 in words is "eighteen million, four hundred fifty-one thousand, nine hundred seventy-three".