2145440254 has 4 divisors (see below), whose sum is σ = 3218160384. Its totient is φ = 1072720126.

The previous prime is 2145440243. The next prime is 2145440257. The reversal of 2145440254 is 4520445412.

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

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2145440257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 536360062 + ... + 536360065.

It is an arithmetic number, because the mean of its divisors is an integer number (804540096).

Almost surely, 2^2145440254 is an apocalyptic number.

2145440254 is a deficient number, since it is larger than the sum of its proper divisors (1072720130).

2145440254 is a wasteful number, since it uses less digits than its factorization.

2145440254 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1072720129.

The product of its (nonzero) digits is 25600, while the sum is 31.

The square root of 2145440254 is about 46318.8973746137. The cubic root of 2145440254 is about 1289.7498170756.

Adding to 2145440254 its reverse (4520445412), we get a palindrome (6665885666).

The spelling of 2145440254 in words is "two billion, one hundred forty-five million, four hundred forty thousand, two hundred fifty-four".