642161228 has 6 divisors (see below), whose sum is σ = 1123782156. Its totient is φ = 321080612.

The previous prime is 642161227. The next prime is 642161237. The reversal of 642161228 is 822161246.

It is a junction number, because it is equal to n+sod(n) for n = 642161194 and 642161203.

It is not an unprimeable number, because it can be changed into a prime (642161227) by changing a digit.

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 as a sum of consecutive naturals, namely, 80270150 + ... + 80270157.

It is an arithmetic number, because the mean of its divisors is an integer number (187297026).

Almost surely, 2^642161228 is an apocalyptic number.

It is an amenable number.

642161228 is a deficient number, since it is larger than the sum of its proper divisors (481620928).

642161228 is a wasteful number, since it uses less digits than its factorization.

642161228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160540311 (or 160540309 counting only the distinct ones).

The product of its digits is 9216, while the sum is 32.

The square root of 642161228 is about 25340.9002997131. The cubic root of 642161228 is about 862.7428329203.

The spelling of 642161228 in words is "six hundred forty-two million, one hundred sixty-one thousand, two hundred twenty-eight".