161055557 has 8 divisors (see below), whose sum is σ = 175394520. Its totient is φ = 146995200.

The previous prime is 161055551. The next prime is 161055563. The reversal of 161055557 is 755550161.

It is an interprime number because it is at equal distance from previous prime (161055551) and next prime (161055563).

It can be written as a sum of positive squares in 4 ways, for example, as 1437601 + 159617956 = 1199^2 + 12634^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 161055557 - 2⁴ = 161055541 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161055551) 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, 68444 + ... + 70757.

It is an arithmetic number, because the mean of its divisors is an integer number (21924315).

Almost surely, 2^161055557 is an apocalyptic number.

It is an amenable number.

161055557 is a deficient number, since it is larger than the sum of its proper divisors (14338963).

161055557 is a wasteful number, since it uses less digits than its factorization.

161055557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139303.

The product of its (nonzero) digits is 26250, while the sum is 35.

The square root of 161055557 is about 12690.7666041102. The cubic root of 161055557 is about 544.0747502620.

The spelling of 161055557 in words is "one hundred sixty-one million, fifty-five thousand, five hundred fifty-seven".