1661746161 has 8 divisors (see below), whose sum is σ = 2215850560. Its totient is φ = 1107736272.

The previous prime is 1661746157. The next prime is 1661746169. The reversal of 1661746161 is 1616471661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1661746161 - 2² = 1661746157 is a prime.

It is a super-2 number, since 2×1661746161² = 5522800607196475842, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1661746169) 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, 51831 + ... + 77523.

It is an arithmetic number, because the mean of its divisors is an integer number (276981320).

Almost surely, 2^1661746161 is an apocalyptic number.

It is an amenable number.

1661746161 is a deficient number, since it is larger than the sum of its proper divisors (554104399).

1661746161 is a wasteful number, since it uses less digits than its factorization.

1661746161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47255.

The product of its digits is 36288, while the sum is 39.

The square root of 1661746161 is about 40764.5208606700. The cubic root of 1661746161 is about 1184.4631704686.

The spelling of 1661746161 in words is "one billion, six hundred sixty-one million, seven hundred forty-six thousand, one hundred sixty-one".