155170661 has 4 divisors (see below), whose sum is σ = 155196012. Its totient is φ = 155145312.

The previous prime is 155170607. The next prime is 155170667. The reversal of 155170661 is 166071551.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 84088900 + 71081761 = 9170^2 + 8431^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-155170661 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 (155170667) 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, 2825 + ... + 17841.

It is an arithmetic number, because the mean of its divisors is an integer number (38799003).

Almost surely, 2^155170661 is an apocalyptic number.

It is an amenable number.

155170661 is a deficient number, since it is larger than the sum of its proper divisors (25351).

155170661 is a wasteful number, since it uses less digits than its factorization.

155170661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25350.

The product of its (nonzero) digits is 6300, while the sum is 32.

The square root of 155170661 is about 12456.7516231159. The cubic root of 155170661 is about 537.3656109667.

The spelling of 155170661 in words is "one hundred fifty-five million, one hundred seventy thousand, six hundred sixty-one".