123451643 has 4 divisors (see below), whose sum is σ = 141087600. Its totient is φ = 105815688.

The previous prime is 123451631. The next prime is 123451661. The reversal of 123451643 is 346154321.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 346154321 = 61 ⋅5674661.

It is a cyclic number.

It is not a de Polignac number, because 123451643 - 2¹⁴ = 123435259 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (123451613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8817968 + ... + 8817981.

It is an arithmetic number, because the mean of its divisors is an integer number (35271900).

Almost surely, 2^123451643 is an apocalyptic number.

123451643 is a deficient number, since it is larger than the sum of its proper divisors (17635957).

123451643 is an equidigital number, since it uses as much as digits as its factorization.

123451643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17635956.

The product of its digits is 8640, while the sum is 29.

The square root of 123451643 is about 11110.8794881413. The cubic root of 123451643 is about 497.9269407294.

The spelling of 123451643 in words is "one hundred twenty-three million, four hundred fifty-one thousand, six hundred forty-three".