721922 has 12 divisors (see below), whose sum is σ = 1151250. Its totient is φ = 339456.

The previous prime is 721921. The next prime is 721951. The reversal of 721922 is 229127.

It can be written as a sum of positive squares in 3 ways, for example, as 707281 + 14641 = 841^2 + 121^2 .

It is not an unprimeable number, because it can be changed into a prime (721921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 47 + ... + 1202.

2⁷²¹⁹²² is an apocalyptic number.

721922 is a deficient number, since it is larger than the sum of its proper divisors (429328).

721922 is a wasteful number, since it uses less digits than its factorization.

721922 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1285 (or 1268 counting only the distinct ones).

The product of its digits is 504, while the sum is 23.

The square root of 721922 is about 849.6599319728. The cubic root of 721922 is about 89.7077764780.

It can be divided in two parts, 72 and 1922, that multiplied together give a square (138384 = 372²).

The spelling of 721922 in words is "seven hundred twenty-one thousand, nine hundred twenty-two".