661378228 has 24 divisors (see below), whose sum is σ = 1328258624. Its totient is φ = 282268800.

The previous prime is 661378213. The next prime is 661378229. The reversal of 661378228 is 822873166.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661378229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42258 + ... + 55753.

Almost surely, 2^661378228 is an apocalyptic number.

It is an amenable number.

661378228 is an abundant number, since it is smaller than the sum of its proper divisors (666880396).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

661378228 is a wasteful number, since it uses less digits than its factorization.

661378228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98263 (or 98261 counting only the distinct ones).

The product of its digits is 193536, while the sum is 43.

The square root of 661378228 is about 25717.2748945140. The cubic root of 661378228 is about 871.2643913373.

The spelling of 661378228 in words is "six hundred sixty-one million, three hundred seventy-eight thousand, two hundred twenty-eight".