253207021 has 16 divisors (see below), whose sum is σ = 269736768. Its totient is φ = 237340800.

The previous prime is 253207013. The next prime is 253207037. The reversal of 253207021 is 120702352.

It is not a de Polignac number, because 253207021 - 2³ = 253207013 is a prime.

It is a super-2 number, since 2×253207021² = 128227590967388882, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 253206983 and 253207001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (253207051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 124906 + ... + 126916.

It is an arithmetic number, because the mean of its divisors is an integer number (16858548).

Almost surely, 2^253207021 is an apocalyptic number.

It is an amenable number.

253207021 is a deficient number, since it is larger than the sum of its proper divisors (16529747).

253207021 is a wasteful number, since it uses less digits than its factorization.

253207021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2172.

The product of its (nonzero) digits is 840, while the sum is 22.

The square root of 253207021 is about 15912.4800392648. The cubic root of 253207021 is about 632.6428167243.

Adding to 253207021 its reverse (120702352), we get a palindrome (373909373).

The spelling of 253207021 in words is "two hundred fifty-three million, two hundred seven thousand, twenty-one".