643073437 has 4 divisors (see below), whose sum is σ = 652671616. Its totient is φ = 633475260.

The previous prime is 643073429. The next prime is 643073441. The reversal of 643073437 is 734370346.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 643073437 - 2³ = 643073429 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 643073396 and 643073405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643073447) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4798989 + ... + 4799122.

It is an arithmetic number, because the mean of its divisors is an integer number (163167904).

Almost surely, 2^643073437 is an apocalyptic number.

643073437 is a gapful number since it is divisible by the number (67) formed by its first and last digit.

It is an amenable number.

643073437 is a deficient number, since it is larger than the sum of its proper divisors (9598179).

643073437 is an equidigital number, since it uses as much as digits as its factorization.

643073437 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9598178.

The product of its (nonzero) digits is 127008, while the sum is 37.

The square root of 643073437 is about 25358.8926611554. The cubic root of 643073437 is about 863.1511568652.

The spelling of 643073437 in words is "six hundred forty-three million, seventy-three thousand, four hundred thirty-seven".