154661 has 4 divisors (see below), whose sum is σ = 166572. Its totient is φ = 142752.

The previous prime is 154643. The next prime is 154667. The reversal of 154661 is 166451.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 166451 = 23 ⋅7237.

It can be written as a sum of positive squares in 2 ways, for example, as 101761 + 52900 = 319^2 + 230^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-154661 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 11 and base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (154667) 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, 5936 + ... + 5961.

It is an arithmetic number, because the mean of its divisors is an integer number (41643).

2¹⁵⁴⁶⁶¹ is an apocalyptic number.

It is an amenable number.

154661 is a deficient number, since it is larger than the sum of its proper divisors (11911).

154661 is a wasteful number, since it uses less digits than its factorization.

154661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11910.

The product of its digits is 720, while the sum is 23.

The square root of 154661 is about 393.2696276094. The cubic root of 154661 is about 53.6776636458.

The spelling of 154661 in words is "one hundred fifty-four thousand, six hundred sixty-one".