718521428 has 6 divisors (see below), whose sum is σ = 1257412506. Its totient is φ = 359260712.

The previous prime is 718521421. The next prime is 718521469. The reversal of 718521428 is 824125817.

It can be written as a sum of positive squares in only one way, i.e., 478209424 + 240312004 = 21868^2 + 15502^2 .

It is a junction number, because it is equal to n+sod(n) for n = 718521391 and 718521400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (718521421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 89815175 + ... + 89815182.

It is an arithmetic number, because the mean of its divisors is an integer number (209568751).

Almost surely, 2^718521428 is an apocalyptic number.

It is an amenable number.

718521428 is a deficient number, since it is larger than the sum of its proper divisors (538891078).

718521428 is a wasteful number, since it uses less digits than its factorization.

718521428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179630361 (or 179630359 counting only the distinct ones).

The product of its digits is 35840, while the sum is 38.

The square root of 718521428 is about 26805.2500081607. The cubic root of 718521428 is about 895.6670029715.

The spelling of 718521428 in words is "seven hundred eighteen million, five hundred twenty-one thousand, four hundred twenty-eight".