1561650166 has 16 divisors (see below), whose sum is σ = 2485186560. Its totient is φ = 733902120.

The previous prime is 1561650161. The next prime is 1561650187. The reversal of 1561650166 is 6610561651.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561650161) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 156970 + ... + 166621.

It is an arithmetic number, because the mean of its divisors is an integer number (155324160).

Almost surely, 2^1561650166 is an apocalyptic number.

1561650166 is a deficient number, since it is larger than the sum of its proper divisors (923536394).

1561650166 is a wasteful number, since it uses less digits than its factorization.

1561650166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 323739.

The product of its (nonzero) digits is 32400, while the sum is 37.

The square root of 1561650166 is about 39517.7196457488. The cubic root of 1561650166 is about 1160.1867926504.

The spelling of 1561650166 in words is "one billion, five hundred sixty-one million, six hundred fifty thousand, one hundred sixty-six".