18400573 has 4 divisors (see below), whose sum is σ = 18659808. Its totient is φ = 18141340.

The previous prime is 18400567. The next prime is 18400583. The reversal of 18400573 is 37500481.

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 18400573 - 2⁵ = 18400541 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 (18400523) 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, 129511 + ... + 129652.

It is an arithmetic number, because the mean of its divisors is an integer number (4664952).

Almost surely, 2^18400573 is an apocalyptic number.

It is an amenable number.

18400573 is a deficient number, since it is larger than the sum of its proper divisors (259235).

18400573 is an equidigital number, since it uses as much as digits as its factorization.

18400573 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 259234.

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 18400573 is about 4289.5889080424. The cubic root of 18400573 is about 264.0039647782.

The spelling of 18400573 in words is "eighteen million, four hundred thousand, five hundred seventy-three".