123465721 has 8 divisors (see below), whose sum is σ = 125411400. Its totient is φ = 121535232.

The previous prime is 123465709. The next prime is 123465739. The reversal of 123465721 is 127564321.

It can be written as a sum of positive squares in 4 ways, for example, as 28676025 + 94789696 = 5355^2 + 9736^2 .

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 123465721 - 2¹⁷ = 123334649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (123465751) 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, 13171 + ... + 20503.

It is an arithmetic number, because the mean of its divisors is an integer number (15676425).

Almost surely, 2^123465721 is an apocalyptic number.

It is an amenable number.

123465721 is a deficient number, since it is larger than the sum of its proper divisors (1945679).

123465721 is a wasteful number, since it uses less digits than its factorization.

123465721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7595.

The product of its digits is 10080, while the sum is 31.

The square root of 123465721 is about 11111.5129932876. The cubic root of 123465721 is about 497.9458673008.

The spelling of 123465721 in words is "one hundred twenty-three million, four hundred sixty-five thousand, seven hundred twenty-one".