722138 has 4 divisors (see below), whose sum is σ = 1083210. Its totient is φ = 361068.

The previous prime is 722123. The next prime is 722147. The reversal of 722138 is 831227.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 831227 = 29 ⋅28663.

It can be written as a sum of positive squares in only one way, i.e., 597529 + 124609 = 773^2 + 353^2 .

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 722138.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 180533 + ... + 180536.

2⁷²²¹³⁸ is an apocalyptic number.

722138 is a deficient number, since it is larger than the sum of its proper divisors (361072).

722138 is a wasteful number, since it uses less digits than its factorization.

722138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 361071.

The product of its digits is 672, while the sum is 23.

The square root of 722138 is about 849.7870321439. The cubic root of 722138 is about 89.7167224803.

The spelling of 722138 in words is "seven hundred twenty-two thousand, one hundred thirty-eight".