561669156 has 18 divisors (see below), whose sum is σ = 1419774902. Its totient is φ = 187223040.

The previous prime is 561669133. The next prime is 561669167. The reversal of 561669156 is 651966165.

It can be written as a sum of positive squares in only one way, i.e., 376981056 + 184688100 = 19416^2 + 13590^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 7800925 + ... + 7800996.

Almost surely, 2^561669156 is an apocalyptic number.

It is an amenable number.

561669156 is an abundant number, since it is smaller than the sum of its proper divisors (858105746).

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

561669156 is a wasteful number, since it uses less digits than its factorization.

561669156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15601931 (or 15601926 counting only the distinct ones).

The product of its digits is 291600, while the sum is 45.

The square root of 561669156 is about 23699.5602490848. The cubic root of 561669156 is about 825.0751843326.

The spelling of 561669156 in words is "five hundred sixty-one million, six hundred sixty-nine thousand, one hundred fifty-six".