123748921 has 4 divisors (see below), whose sum is σ = 124262644. Its totient is φ = 123235200.

The previous prime is 123748913. The next prime is 123748951. The reversal of 123748921 is 129847321.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 56836521 + 66912400 = 7539^2 + 8180^2 .

It is a cyclic number.

It is not a de Polignac number, because 123748921 - 2³ = 123748913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (123748951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 256500 + ... + 256981.

It is an arithmetic number, because the mean of its divisors is an integer number (31065661).

Almost surely, 2^123748921 is an apocalyptic number.

It is an amenable number.

123748921 is a deficient number, since it is larger than the sum of its proper divisors (513723).

123748921 is an equidigital number, since it uses as much as digits as its factorization.

123748921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 513722.

The product of its digits is 24192, while the sum is 37.

The square root of 123748921 is about 11124.2492330943. The cubic root of 123748921 is about 498.3262983637.

The spelling of 123748921 in words is "one hundred twenty-three million, seven hundred forty-eight thousand, nine hundred twenty-one".