521393034240 has 880 divisors, whose sum is σ = 2034881465232. Its totient is φ = 126892376064.

The previous prime is 521393034229. The next prime is 521393034311. The reversal of 521393034240 is 42430393125.

521393034240 is a `hidden beast` number, since 5 + 21 + 393 + 0 + 3 + 4 + 240 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 4236447744 + 517156586496 = 65088^2 + 719136^2 .

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 = 521393034195 and 521393034204.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 522961422 + ... + 522962418.

Almost surely, 2^521393034240 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 521393034240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1017440732616).

521393034240 is an abundant number, since it is smaller than the sum of its proper divisors (1513488430992).

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

521393034240 is a wasteful number, since it uses less digits than its factorization.

521393034240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1144 (or 1117 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 36.

The spelling of 521393034240 in words is "five hundred twenty-one billion, three hundred ninety-three million, thirty-four thousand, two hundred forty".