245640121 has 6 divisors (see below), whose sum is σ = 254403422. Its totient is φ = 237168960.

The previous prime is 245640079. The next prime is 245640139. The reversal of 245640121 is 121046542.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 3370896 + 242269225 = 1836^2 + 15565^2 .

It is not a de Polignac number, because 245640121 - 2¹¹ = 245638073 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (245640821) 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, 145200 + ... + 146881.

Almost surely, 2^245640121 is an apocalyptic number.

It is an amenable number.

245640121 is a deficient number, since it is larger than the sum of its proper divisors (8763301).

245640121 is an equidigital number, since it uses as much as digits as its factorization.

245640121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 292139 (or 292110 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 245640121 is about 15672.9104189362. The cubic root of 245640121 is about 626.2769591437.

Adding to 245640121 its reverse (121046542), we get a palindrome (366686663).

The spelling of 245640121 in words is "two hundred forty-five million, six hundred forty thousand, one hundred twenty-one".