123513391 has 2 divisors, whose sum is σ = 123513392. Its totient is φ = 123513390.

The previous prime is 123513359. The next prime is 123513421. The reversal of 123513391 is 193315321.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 123513391 - 2⁵ = 123513359 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (123513311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61756695 + 61756696.

It is an arithmetic number, because the mean of its divisors is an integer number (61756696).

Almost surely, 2^123513391 is an apocalyptic number.

123513391 is the 5941-st centered heptagonal number.

123513391 is a deficient number, since it is larger than the sum of its proper divisors (1).

123513391 is an equidigital number, since it uses as much as digits as its factorization.

123513391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2430, while the sum is 28.

The square root of 123513391 is about 11113.6578586890. The cubic root of 123513391 is about 498.0099445335.

It can be divided in two parts, 123513 and 391, that added together give a square (123904 = 352²).

The spelling of 123513391 in words is "one hundred twenty-three million, five hundred thirteen thousand, three hundred ninety-one".