722161728 has 252 divisors, whose sum is σ = 2294705088. Its totient is φ = 216691200.

The previous prime is 722161703. The next prime is 722161757. The reversal of 722161728 is 827161227.

It is a super-2 number, since 2×722161728² = 1043035122775891968, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 722161692 and 722161701.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 4782453 + ... + 4782603.

Almost surely, 2^722161728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 722161728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1147352544).

722161728 is an abundant number, since it is smaller than the sum of its proper divisors (1572543360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

722161728 is a wasteful number, since it uses less digits than its factorization.

722161728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 230 (or 198 counting only the distinct ones).

The product of its digits is 18816, while the sum is 36.

The square root of 722161728 is about 26873.0669630394. The cubic root of 722161728 is about 897.1770510643.

The spelling of 722161728 in words is "seven hundred twenty-two million, one hundred sixty-one thousand, seven hundred twenty-eight".