155521233 has 12 divisors (see below), whose sum is σ = 256733568. Its totient is φ = 88869240.

The previous prime is 155521211. The next prime is 155521243. The reversal of 155521233 is 332125551.

It is a happy number.

It is not a de Polignac number, because 155521233 - 2⁸ = 155520977 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 155521197 and 155521206.

It is not an unprimeable number, because it can be changed into a prime (155521243) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1234233 + ... + 1234358.

It is an arithmetic number, because the mean of its divisors is an integer number (21394464).

Almost surely, 2^155521233 is an apocalyptic number.

It is an amenable number.

155521233 is a deficient number, since it is larger than the sum of its proper divisors (101212335).

155521233 is a wasteful number, since it uses less digits than its factorization.

155521233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2468604 (or 2468601 counting only the distinct ones).

The product of its digits is 4500, while the sum is 27.

The square root of 155521233 is about 12470.8152500147. The cubic root of 155521233 is about 537.7699907693.

Adding to 155521233 its reverse (332125551), we get a palindrome (487646784).

The spelling of 155521233 in words is "one hundred fifty-five million, five hundred twenty-one thousand, two hundred thirty-three".