124123921 has 4 divisors (see below), whose sum is σ = 124299700. Its totient is φ = 123948144.

The previous prime is 124123913. The next prime is 124123943. The reversal of 124123921 is 129321421.

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 43824400 + 80299521 = 6620^2 + 8961^2 .

It is a cyclic number.

It is not a de Polignac number, because 124123921 - 2³ = 124123913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (124123981) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 86826 + ... + 88243.

It is an arithmetic number, because the mean of its divisors is an integer number (31074925).

Almost surely, 2^124123921 is an apocalyptic number.

It is an amenable number.

124123921 is a deficient number, since it is larger than the sum of its proper divisors (175779).

124123921 is an equidigital number, since it uses as much as digits as its factorization.

124123921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175778.

The product of its digits is 864, while the sum is 25.

The square root of 124123921 is about 11141.0915533443. The cubic root of 124123921 is about 498.8291550510.

The spelling of 124123921 in words is "one hundred twenty-four million, one hundred twenty-three thousand, nine hundred twenty-one".