145621193 has 4 divisors (see below), whose sum is σ = 146463108. Its totient is φ = 144779280.

The previous prime is 145621183. The next prime is 145621237. The reversal of 145621193 is 391126541.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 391126541 = 13 ⋅30086657.

It can be written as a sum of positive squares in 2 ways, for example, as 105842944 + 39778249 = 10288^2 + 6307^2 .

It is a cyclic number.

It is not a de Polignac number, because 145621193 - 2¹² = 145617097 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 (145621123) 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, 420698 + ... + 421043.

It is an arithmetic number, because the mean of its divisors is an integer number (36615777).

Almost surely, 2^145621193 is an apocalyptic number.

It is an amenable number.

145621193 is a deficient number, since it is larger than the sum of its proper divisors (841915).

145621193 is an equidigital number, since it uses as much as digits as its factorization.

145621193 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 841914.

The product of its digits is 6480, while the sum is 32.

The square root of 145621193 is about 12067.3606476313. The cubic root of 145621193 is about 526.1079464924.

The spelling of 145621193 in words is "one hundred forty-five million, six hundred twenty-one thousand, one hundred ninety-three".