1661096605 has 32 divisors (see below), whose sum is σ = 2422379520. Its totient is φ = 1067458560.

The previous prime is 1661096599. The next prime is 1661096609. The reversal of 1661096605 is 5066901661.

It is not a de Polignac number, because 1661096605 - 2⁵ = 1661096573 is a prime.

It is a super-2 number, since 2×1661096605² = 5518483862285052050, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661096609) 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 in 31 ways as a sum of consecutive naturals, for example, 136365 + ... + 148045.

It is an arithmetic number, because the mean of its divisors is an integer number (75699360).

Almost surely, 2^1661096605 is an apocalyptic number.

It is an amenable number.

1661096605 is a deficient number, since it is larger than the sum of its proper divisors (761282915).

1661096605 is a wasteful number, since it uses less digits than its factorization.

1661096605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11949.

The product of its (nonzero) digits is 58320, while the sum is 40.

The square root of 1661096605 is about 40756.5529087041. The cubic root of 1661096605 is about 1184.3088196928.

The spelling of 1661096605 in words is "one billion, six hundred sixty-one million, ninety-six thousand, six hundred five".