123640121 has 8 divisors (see below), whose sum is σ = 139231488. Its totient is φ = 108774000.

The previous prime is 123640109. The next prime is 123640123. The reversal of 123640121 is 121046321.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 123640121 - 2⁶ = 123640057 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 123640093 and 123640102.

It is not an unprimeable number, because it can be changed into a prime (123640123) 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, 180950 + ... + 181631.

It is an arithmetic number, because the mean of its divisors is an integer number (17403936).

Almost surely, 2^123640121 is an apocalyptic number.

123640121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

123640121 is a deficient number, since it is larger than the sum of its proper divisors (15591367).

123640121 is a wasteful number, since it uses less digits than its factorization.

123640121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 362623.

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 123640121 is about 11119.3579400971. The cubic root of 123640121 is about 498.1802127843.

Adding to 123640121 its reverse (121046321), we get a palindrome (244686442).

The spelling of 123640121 in words is "one hundred twenty-three million, six hundred forty thousand, one hundred twenty-one".