18922997 has 4 divisors (see below), whose sum is σ = 19745760. Its totient is φ = 18100236.

The previous prime is 18922931. The next prime is 18923039. The reversal of 18922997 is 79922981.

It is a happy number.

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: 79922981 = 41 ⋅1949341.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18922997 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 (18922907) 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, 411347 + ... + 411392.

It is an arithmetic number, because the mean of its divisors is an integer number (4936440).

Almost surely, 2^18922997 is an apocalyptic number.

It is an amenable number.

18922997 is a deficient number, since it is larger than the sum of its proper divisors (822763).

18922997 is an equidigital number, since it uses as much as digits as its factorization.

18922997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 822762.

The product of its digits is 163296, while the sum is 47.

The square root of 18922997 is about 4350.0571260617. The cubic root of 18922997 is about 266.4791944493.

The spelling of 18922997 in words is "eighteen million, nine hundred twenty-two thousand, nine hundred ninety-seven".