123545551 has 2 divisors, whose sum is σ = 123545552. Its totient is φ = 123545550.

The previous prime is 123545537. The next prime is 123545561. The reversal of 123545551 is 155545321.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123545551 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (123545561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61772775 + 61772776.

It is an arithmetic number, because the mean of its divisors is an integer number (61772776).

Almost surely, 2^123545551 is an apocalyptic number.

123545551 is a deficient number, since it is larger than the sum of its proper divisors (1).

123545551 is an equidigital number, since it uses as much as digits as its factorization.

123545551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15000, while the sum is 31.

The square root of 123545551 is about 11115.1046328858. The cubic root of 123545551 is about 498.0531641656.

The spelling of 123545551 in words is "one hundred twenty-three million, five hundred forty-five thousand, five hundred fifty-one".