1251533123 has 2 divisors, whose sum is σ = 1251533124. Its totient is φ = 1251533122.

The previous prime is 1251533119. The next prime is 1251533137. The reversal of 1251533123 is 3213351521.

It is a weak prime.

It is an emirp because it is prime and its reverse (3213351521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1251533123 - 2² = 1251533119 is a prime.

It is a super-2 number, since 2×1251533123² = 3132670315932266258, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1251533092 and 1251533101.

It is not a weakly prime, because it can be changed into another prime (1251533113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 625766561 + 625766562.

It is an arithmetic number, because the mean of its divisors is an integer number (625766562).

Almost surely, 2^1251533123 is an apocalyptic number.

1251533123 is a deficient number, since it is larger than the sum of its proper divisors (1).

1251533123 is an equidigital number, since it uses as much as digits as its factorization.

1251533123 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2700, while the sum is 26.

The square root of 1251533123 is about 35377.0140486729. The cubic root of 1251533123 is about 1077.6575668712.

Adding to 1251533123 its reverse (3213351521), we get a palindrome (4464884644).

The spelling of 1251533123 in words is "one billion, two hundred fifty-one million, five hundred thirty-three thousand, one hundred twenty-three".