123406551 has 8 divisors (see below), whose sum is σ = 182824560. Its totient is φ = 82271016.

The previous prime is 123406531. The next prime is 123406559. The reversal of 123406551 is 155604321.

123406551 is a `hidden beast` number, since 1 + 2 + 3 + 4 + 0 + 655 + 1 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-123406551 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 4570613 = 123406551 / (1 + 2 + 3 + 4 + 0 + 6 + 5 + 5 + 1).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123406559) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2285280 + ... + 2285333.

It is an arithmetic number, because the mean of its divisors is an integer number (22853070).

Almost surely, 2^123406551 is an apocalyptic number.

123406551 is a deficient number, since it is larger than the sum of its proper divisors (59418009).

123406551 is an equidigital number, since it uses as much as digits as its factorization.

123406551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4570622 (or 4570616 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 123406551 is about 11108.8501205120. The cubic root of 123406551 is about 497.8663090108.

The spelling of 123406551 in words is "one hundred twenty-three million, four hundred six thousand, five hundred fifty-one".