721291061 has 8 divisors (see below), whose sum is σ = 744930720. Its totient is φ = 697869648.

The previous prime is 721291057. The next prime is 721291097. The reversal of 721291061 is 160192127.

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 721291061 - 2² = 721291057 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721291031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47831 + ... + 61076.

It is an arithmetic number, because the mean of its divisors is an integer number (93116340).

Almost surely, 2^721291061 is an apocalyptic number.

It is an amenable number.

721291061 is a deficient number, since it is larger than the sum of its proper divisors (23639659).

721291061 is a wasteful number, since it uses less digits than its factorization.

721291061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109123.

The product of its (nonzero) digits is 1512, while the sum is 29.

The square root of 721291061 is about 26856.8624563630. The cubic root of 721291061 is about 896.8163485803.

The spelling of 721291061 in words is "seven hundred twenty-one million, two hundred ninety-one thousand, sixty-one".