245306021 has 4 divisors (see below), whose sum is σ = 246406272. Its totient is φ = 244205772.

The previous prime is 245306003. The next prime is 245306027. The reversal of 245306021 is 120603542.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-245306021 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (245306027) 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, 549791 + ... + 550236.

It is an arithmetic number, because the mean of its divisors is an integer number (61601568).

Almost surely, 2^245306021 is an apocalyptic number.

It is an amenable number.

245306021 is a deficient number, since it is larger than the sum of its proper divisors (1100251).

245306021 is a wasteful number, since it uses less digits than its factorization.

245306021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1100250.

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 245306021 is about 15662.2482741144. The cubic root of 245306021 is about 625.9928930794.

Adding to 245306021 its reverse (120603542), we get a palindrome (365909563).

The spelling of 245306021 in words is "two hundred forty-five million, three hundred six thousand, twenty-one".