145555331 has 4 divisors (see below), whose sum is σ = 148301712. Its totient is φ = 142808952.

The previous prime is 145555303. The next prime is 145555337. The reversal of 145555331 is 133555541.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 145555331 - 2¹⁴ = 145538947 is a prime.

It is a super-2 number, since 2×145555331² = 42372708765039122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (145555337) 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, 1373111 + ... + 1373216.

It is an arithmetic number, because the mean of its divisors is an integer number (37075428).

Almost surely, 2^145555331 is an apocalyptic number.

145555331 is a deficient number, since it is larger than the sum of its proper divisors (2746381).

145555331 is an equidigital number, since it uses as much as digits as its factorization.

145555331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2746380.

The product of its digits is 22500, while the sum is 32.

The square root of 145555331 is about 12064.6314075483. The cubic root of 145555331 is about 526.0286179594.

The spelling of 145555331 in words is "one hundred forty-five million, five hundred fifty-five thousand, three hundred thirty-one".