1665566610 has 32 divisors (see below), whose sum is σ = 4007162880. Its totient is φ = 443061888.

The previous prime is 1665566603. The next prime is 1665566611. The reversal of 1665566610 is 166655661.

It is a super-2 number, since 2×1665566610² = 5548224264693784200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1665566611) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55602 + ... + 80141.

It is an arithmetic number, because the mean of its divisors is an integer number (125223840).

Almost surely, 2^1665566610 is an apocalyptic number.

1665566610 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1665566610 is an abundant number, since it is smaller than the sum of its proper divisors (2341596270).

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

1665566610 is a wasteful number, since it uses less digits than its factorization.

1665566610 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136162.

The product of its (nonzero) digits is 194400, while the sum is 42.

The square root of 1665566610 is about 40811.3539349039. The cubic root of 1665566610 is about 1185.3701918057.

It can be divided in two parts, 166556 and 6610, that added together give a triangular number (173166 = T₅₈₈).

The spelling of 1665566610 in words is "one billion, six hundred sixty-five million, five hundred sixty-six thousand, six hundred ten".