661425188 has 24 divisors (see below), whose sum is σ = 1290088800. Its totient is φ = 294876288.

The previous prime is 661425179. The next prime is 661425199. The reversal of 661425188 is 881524166.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 254678 + ... + 257261.

It is an arithmetic number, because the mean of its divisors is an integer number (53753700).

Almost surely, 2^661425188 is an apocalyptic number.

661425188 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

661425188 is a deficient number, since it is larger than the sum of its proper divisors (628663612).

661425188 is a wasteful number, since it uses less digits than its factorization.

661425188 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 511979 (or 511977 counting only the distinct ones).

The product of its digits is 92160, while the sum is 41.

The square root of 661425188 is about 25718.1878832860. The cubic root of 661425188 is about 871.2850117155.

The spelling of 661425188 in words is "six hundred sixty-one million, four hundred twenty-five thousand, one hundred eighty-eight".