723122221 has 8 divisors (see below), whose sum is σ = 748513080. Its totient is φ = 697761792.

The previous prime is 723122219. The next prime is 723122237. The reversal of 723122221 is 122221327.

It can be written as a sum of positive squares in 4 ways, for example, as 265225 + 722856996 = 515^2 + 26886^2 .

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 723122221 - 2¹ = 723122219 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 723122192 and 723122201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (723122201) 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, 47661 + ... + 60973.

It is an arithmetic number, because the mean of its divisors is an integer number (93564135).

Almost surely, 2^723122221 is an apocalyptic number.

It is an amenable number.

723122221 is a deficient number, since it is larger than the sum of its proper divisors (25390859).

723122221 is a wasteful number, since it uses less digits than its factorization.

723122221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15215.

The product of its digits is 672, while the sum is 22.

The square root of 723122221 is about 26890.9319474056. The cubic root of 723122221 is about 897.5746307588.

Adding to 723122221 its reverse (122221327), we get a palindrome (845343548).

The spelling of 723122221 in words is "seven hundred twenty-three million, one hundred twenty-two thousand, two hundred twenty-one".