251228123 has 4 divisors (see below), whose sum is σ = 259332288. Its totient is φ = 243123960.

The previous prime is 251228101. The next prime is 251228143. The reversal of 251228123 is 321822152.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 251228123 - 2²² = 247033819 is a prime.

It is a super-2 number, since 2×251228123² = 126231139572206258, 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 = 251228092 and 251228101.

It is not an unprimeable number, because it can be changed into a prime (251228143) 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, 4052036 + ... + 4052097.

It is an arithmetic number, because the mean of its divisors is an integer number (64833072).

Almost surely, 2^251228123 is an apocalyptic number.

251228123 is a deficient number, since it is larger than the sum of its proper divisors (8104165).

251228123 is an equidigital number, since it uses as much as digits as its factorization.

251228123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8104164.

The product of its digits is 1920, while the sum is 26.

The square root of 251228123 is about 15850.1773807109. The cubic root of 251228123 is about 630.9903990475.

The spelling of 251228123 in words is "two hundred fifty-one million, two hundred twenty-eight thousand, one hundred twenty-three".