643252572040 has 32 divisors (see below), whose sum is σ = 1558650464280. Its totient is φ = 237508641792.

The previous prime is 643252572031. The next prime is 643252572041. The reversal of 643252572040 is 40275252346.

It is a happy number.

643252572040 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 371463432484 + 271789139556 = 609478^2 + 521334^2 .

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 643252571984 and 643252572002.

It is not an unprimeable number, because it can be changed into a prime (643252572041) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 618511569 + ... + 618512608.

Almost surely, 2^643252572040 is an apocalyptic number.

It is an amenable number.

643252572040 is an abundant number, since it is smaller than the sum of its proper divisors (915397892240).

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

643252572040 is a wasteful number, since it uses less digits than its factorization.

643252572040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1237024201 (or 1237024197 counting only the distinct ones).

The product of its (nonzero) digits is 403200, while the sum is 40.

The spelling of 643252572040 in words is "six hundred forty-three billion, two hundred fifty-two million, five hundred seventy-two thousand, forty".