198815651 has 4 divisors (see below), whose sum is σ = 198845400. Its totient is φ = 198785904.

The previous prime is 198815621. The next prime is 198815693. The reversal of 198815651 is 156518891.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 198815651 - 2¹⁴ = 198799267 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (198815621) 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, 335 + ... + 19943.

It is an arithmetic number, because the mean of its divisors is an integer number (49711350).

Almost surely, 2^198815651 is an apocalyptic number.

198815651 is a deficient number, since it is larger than the sum of its proper divisors (29749).

198815651 is a wasteful number, since it uses less digits than its factorization.

198815651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29748.

The product of its digits is 86400, while the sum is 44.

The square root of 198815651 is about 14100.2003886470. The cubic root of 198815651 is about 583.6469090282.

The spelling of 198815651 in words is "one hundred ninety-eight million, eight hundred fifteen thousand, six hundred fifty-one".