1251320131 has 4 divisors (see below), whose sum is σ = 1285139632. Its totient is φ = 1217500632.

The previous prime is 1251320093. The next prime is 1251320141. The reversal of 1251320131 is 1310231521.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1310231521 = 73 ⋅17948377.

It is a cyclic number.

It is not a de Polignac number, because 1251320131 - 2²¹ = 1249222979 is a prime.

It is a super-2 number, since 2×1251320131² = 3131604140491714322, 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 = 1251320099 and 1251320108.

It is not an unprimeable number, because it can be changed into a prime (1251320141) 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 in 3 ways as a sum of consecutive naturals, for example, 16909695 + ... + 16909768.

It is an arithmetic number, because the mean of its divisors is an integer number (321284908).

Almost surely, 2^1251320131 is an apocalyptic number.

1251320131 is a deficient number, since it is larger than the sum of its proper divisors (33819501).

1251320131 is an equidigital number, since it uses as much as digits as its factorization.

1251320131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33819500.

The product of its (nonzero) digits is 180, while the sum is 19.

The square root of 1251320131 is about 35374.0036043420. The cubic root of 1251320131 is about 1077.5964297324.

Adding to 1251320131 its reverse (1310231521), we get a palindrome (2561551652).

The spelling of 1251320131 in words is "one billion, two hundred fifty-one million, three hundred twenty thousand, one hundred thirty-one".