245305021 has 6 divisors (see below), whose sum is σ = 265626330. Its totient is φ = 226435248.

The previous prime is 245305007. The next prime is 245305031. The reversal of 245305021 is 120503542.

It can be written as a sum of positive squares in 3 ways, for example, as 30360100 + 214944921 = 5510^2 + 14661^2 .

It is not a de Polignac number, because 245305021 - 2¹³ = 245296829 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 245304983 and 245305001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (245305031) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 725586 + ... + 725923.

It is an arithmetic number, because the mean of its divisors is an integer number (44271055).

Almost surely, 2^245305021 is an apocalyptic number.

It is an amenable number.

245305021 is a deficient number, since it is larger than the sum of its proper divisors (20321309).

245305021 is a wasteful number, since it uses less digits than its factorization.

245305021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1451535 (or 1451522 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 22.

The square root of 245305021 is about 15662.2163501849. The cubic root of 245305021 is about 625.9920424497.

Adding to 245305021 its reverse (120503542), we get a palindrome (365808563).

The spelling of 245305021 in words is "two hundred forty-five million, three hundred five thousand, twenty-one".