198717451 has 2 divisors, whose sum is σ = 198717452. Its totient is φ = 198717450.

The previous prime is 198717433. The next prime is 198717503. The reversal of 198717451 is 154717891.

It is a weak prime.

It is an emirp because it is prime and its reverse (154717891) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 198717451 - 2⁹ = 198716939 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 198717398 and 198717407.

It is not a weakly prime, because it can be changed into another prime (198717151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99358725 + 99358726.

It is an arithmetic number, because the mean of its divisors is an integer number (99358726).

Almost surely, 2^198717451 is an apocalyptic number.

198717451 is a deficient number, since it is larger than the sum of its proper divisors (1).

198717451 is an equidigital number, since it uses as much as digits as its factorization.

198717451 is an evil number, because the sum of its binary digits is even.

The product of its digits is 70560, while the sum is 43.

The square root of 198717451 is about 14096.7177385376. The cubic root of 198717451 is about 583.5508006231.

Subtracting from 198717451 its product of digits (70560), we obtain a palindrome (198646891).

The spelling of 198717451 in words is "one hundred ninety-eight million, seven hundred seventeen thousand, four hundred fifty-one".