660161533 has 4 divisors (see below), whose sum is σ = 666967420. Its totient is φ = 653355648.

The previous prime is 660161507. The next prime is 660161543. The reversal of 660161533 is 335161066.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 335161066 = 2 ⋅167580533.

It can be written as a sum of positive squares in 2 ways, for example, as 112741924 + 547419609 = 10618^2 + 23397^2 .

It is a cyclic number.

It is not a de Polignac number, because 660161533 - 2⁵ = 660161501 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 660161495 and 660161504.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660161503) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3402798 + ... + 3402991.

It is an arithmetic number, because the mean of its divisors is an integer number (166741855).

Almost surely, 2^660161533 is an apocalyptic number.

It is an amenable number.

660161533 is a deficient number, since it is larger than the sum of its proper divisors (6805887).

660161533 is an equidigital number, since it uses as much as digits as its factorization.

660161533 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6805886.

The product of its (nonzero) digits is 9720, while the sum is 31.

The square root of 660161533 is about 25693.6087967417. The cubic root of 660161533 is about 870.7297936885.

The spelling of 660161533 in words is "six hundred sixty million, one hundred sixty-one thousand, five hundred thirty-three".