1661036165 has 32 divisors (see below), whose sum is σ = 2087824896. Its totient is φ = 1267568640.

The previous prime is 1661036159. The next prime is 1661036177. The reversal of 1661036165 is 5616301661.

It is not a de Polignac number, because 1661036165 - 2⁶ = 1661036101 is a prime.

It is a super-2 number, since 2×1661036165² = 5518082282875814450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2403470 + ... + 2404160.

It is an arithmetic number, because the mean of its divisors is an integer number (65244528).

Almost surely, 2^1661036165 is an apocalyptic number.

It is an amenable number.

1661036165 is a deficient number, since it is larger than the sum of its proper divisors (426788731).

1661036165 is a wasteful number, since it uses less digits than its factorization.

1661036165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 989.

The product of its (nonzero) digits is 19440, while the sum is 35.

The square root of 1661036165 is about 40755.8114261022. The cubic root of 1661036165 is about 1184.2944555888.

The spelling of 1661036165 in words is "one billion, six hundred sixty-one million, thirty-six thousand, one hundred sixty-five".