724378921 has 8 divisors (see below), whose sum is σ = 837164160. Its totient is φ = 613919328.

The previous prime is 724378913. The next prime is 724378943. The reversal of 724378921 is 129873427.

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 724378921 - 2³ = 724378913 is a prime.

It is not an unprimeable number, because it can be changed into a prime (724378121) 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, 580741 + ... + 581986.

It is an arithmetic number, because the mean of its divisors is an integer number (104645520).

Almost surely, 2^724378921 is an apocalyptic number.

It is an amenable number.

724378921 is a deficient number, since it is larger than the sum of its proper divisors (112785239).

724378921 is a wasteful number, since it uses less digits than its factorization.

724378921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1162823.

The product of its digits is 169344, while the sum is 43.

The square root of 724378921 is about 26914.2884171215. The cubic root of 724378921 is about 898.0942889868.

The spelling of 724378921 in words is "seven hundred twenty-four million, three hundred seventy-eight thousand, nine hundred twenty-one".