722818 has 4 divisors (see below), whose sum is σ = 1084230. Its totient is φ = 361408.

The previous prime is 722807. The next prime is 722819. The reversal of 722818 is 818227.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 818227 = 17 ⋅48131.

It can be written as a sum of positive squares in only one way, i.e., 573049 + 149769 = 757^2 + 387^2 .

It is a super-2 number, since 2×722818² = 1044931722248, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (722819) by changing a digit.

722818 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 180703 + ... + 180706.

2⁷²²⁸¹⁸ is an apocalyptic number.

722818 is a deficient number, since it is larger than the sum of its proper divisors (361412).

722818 is a wasteful number, since it uses less digits than its factorization.

722818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 361411.

The product of its digits is 1792, while the sum is 28.

The square root of 722818 is about 850.1870382451. The cubic root of 722818 is about 89.7448741780.

It can be divided in two parts, 722 and 818, that added together give a triangular number (1540 = T₅₅).

The spelling of 722818 in words is "seven hundred twenty-two thousand, eight hundred eighteen".