145993591 has 4 divisors (see below), whose sum is σ = 146031192. Its totient is φ = 145955992.

The previous prime is 145993583. The next prime is 145993607. The reversal of 145993591 is 195399541.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 195399541 = 31 ⋅6303211.

It is a cyclic number.

It is not a de Polignac number, because 145993591 - 2³ = 145993583 is a prime.

It is a super-2 number, since 2×145993591² = 42628257226150562, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (145993531) 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, 12205 + ... + 20998.

It is an arithmetic number, because the mean of its divisors is an integer number (36507798).

Almost surely, 2^145993591 is an apocalyptic number.

145993591 is a deficient number, since it is larger than the sum of its proper divisors (37601).

145993591 is an equidigital number, since it uses as much as digits as its factorization.

145993591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37600.

The product of its digits is 218700, while the sum is 46.

The square root of 145993591 is about 12082.7807643770. The cubic root of 145993591 is about 526.5560378025.

The spelling of 145993591 in words is "one hundred forty-five million, nine hundred ninety-three thousand, five hundred ninety-one".