253106021 has 6 divisors (see below), whose sum is σ = 294429510. Its totient is φ = 216947976.

The previous prime is 253106003. The next prime is 253106023. The reversal of 253106021 is 120601352.

It can be written as a sum of positive squares in only one way, i.e., 159112996 + 93993025 = 12614^2 + 9695^2 .

It is not a de Polignac number, because 253106021 - 2¹⁰ = 253104997 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 253105984 and 253106002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (253106023) 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, 2582666 + ... + 2582763.

It is an arithmetic number, because the mean of its divisors is an integer number (49071585).

Almost surely, 2^253106021 is an apocalyptic number.

It is an amenable number.

253106021 is a deficient number, since it is larger than the sum of its proper divisors (41323489).

253106021 is an equidigital number, since it uses as much as digits as its factorization.

253106021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5165443 (or 5165436 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 253106021 is about 15909.3061130899. The cubic root of 253106021 is about 632.5586886962.

Adding to 253106021 its reverse (120601352), we get a palindrome (373707373).

The spelling of 253106021 in words is "two hundred fifty-three million, one hundred six thousand, twenty-one".