123655531 has 2 divisors, whose sum is σ = 123655532. Its totient is φ = 123655530.

The previous prime is 123655523. The next prime is 123655541. The reversal of 123655531 is 135556321.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 123655531 - 2³ = 123655523 is a prime.

It is a super-2 number, since 2×123655531² = 30581380693783922, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 123655493 and 123655502.

It is not a weakly prime, because it can be changed into another prime (123655541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61827765 + 61827766.

It is an arithmetic number, because the mean of its divisors is an integer number (61827766).

Almost surely, 2^123655531 is an apocalyptic number.

123655531 is a deficient number, since it is larger than the sum of its proper divisors (1).

123655531 is an equidigital number, since it uses as much as digits as its factorization.

123655531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13500, while the sum is 31.

The square root of 123655531 is about 11120.0508542003. The cubic root of 123655531 is about 498.2009089739.

The spelling of 123655531 in words is "one hundred twenty-three million, six hundred fifty-five thousand, five hundred thirty-one".