154113521 has 4 divisors (see below), whose sum is σ = 154243044. Its totient is φ = 153984000.

The previous prime is 154113497. The next prime is 154113539. The reversal of 154113521 is 125311451.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 125311451 = 53 ⋅2364367.

It can be written as a sum of positive squares in 2 ways, for example, as 17106496 + 137007025 = 4136^2 + 11705^2 .

It is a cyclic number.

It is not a de Polignac number, because 154113521 - 2¹⁴ = 154097137 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (154113571) 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, 62960 + ... + 65361.

It is an arithmetic number, because the mean of its divisors is an integer number (38560761).

Almost surely, 2^154113521 is an apocalyptic number.

It is an amenable number.

154113521 is a deficient number, since it is larger than the sum of its proper divisors (129523).

154113521 is a wasteful number, since it uses less digits than its factorization.

154113521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129522.

The product of its digits is 600, while the sum is 23.

The square root of 154113521 is about 12414.2466948261. The cubic root of 154113521 is about 536.1425154284.

Adding to 154113521 its reverse (125311451), we get a palindrome (279424972).

The spelling of 154113521 in words is "one hundred fifty-four million, one hundred thirteen thousand, five hundred twenty-one".