145972394 has 4 divisors (see below), whose sum is σ = 218958594. Its totient is φ = 72986196.

The previous prime is 145972381. The next prime is 145972439. The reversal of 145972394 is 493279541.

145972394 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 493279541 = 83 ⋅5943127.

It can be written as a sum of positive squares in only one way, i.e., 104305369 + 41667025 = 10213^2 + 6455^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36493097 + ... + 36493100.

Almost surely, 2^145972394 is an apocalyptic number.

145972394 is a deficient number, since it is larger than the sum of its proper divisors (72986200).

145972394 is an equidigital number, since it uses as much as digits as its factorization.

145972394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72986199.

The product of its digits is 272160, while the sum is 44.

The square root of 145972394 is about 12081.9035751822. The cubic root of 145972394 is about 526.5305527830.

The spelling of 145972394 in words is "one hundred forty-five million, nine hundred seventy-two thousand, three hundred ninety-four".