661551422 has 32 divisors (see below), whose sum is σ = 1179878400. Its totient is φ = 272186208.

The previous prime is 661551419. The next prime is 661551427. The reversal of 661551422 is 224155166.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661551427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 68123 + ... + 77225.

It is an arithmetic number, because the mean of its divisors is an integer number (36871200).

Almost surely, 2^661551422 is an apocalyptic number.

661551422 is a deficient number, since it is larger than the sum of its proper divisors (518326978).

661551422 is a wasteful number, since it uses less digits than its factorization.

661551422 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9320.

The product of its digits is 14400, while the sum is 32.

The square root of 661551422 is about 25720.6419437774. The cubic root of 661551422 is about 871.3404368781.

The spelling of 661551422 in words is "six hundred sixty-one million, five hundred fifty-one thousand, four hundred twenty-two".