721412021 has 8 divisors (see below), whose sum is σ = 787299744. Its totient is φ = 655575120.

The previous prime is 721412011. The next prime is 721412039. The reversal of 721412021 is 120214127.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-721412021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 721411984 and 721412002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721412011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20846 + ... + 43328.

It is an arithmetic number, because the mean of its divisors is an integer number (98412468).

Almost surely, 2^721412021 is an apocalyptic number.

It is an amenable number.

721412021 is a deficient number, since it is larger than the sum of its proper divisors (65887723).

721412021 is a wasteful number, since it uses less digits than its factorization.

721412021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25411.

The product of its (nonzero) digits is 224, while the sum is 20.

The square root of 721412021 is about 26859.1143003637. The cubic root of 721412021 is about 896.8664776003.

Adding to 721412021 its reverse (120214127), we get a palindrome (841626148).

The spelling of 721412021 in words is "seven hundred twenty-one million, four hundred twelve thousand, twenty-one".