643469280 has 48 divisors (see below), whose sum is σ = 2026929744. Its totient is φ = 171591680.

The previous prime is 643469279. The next prime is 643469287. The reversal of 643469280 is 82964346.

It is a happy number.

643469280 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643469287) 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, 669801 + ... + 670760.

It is an arithmetic number, because the mean of its divisors is an integer number (42227703).

Almost surely, 2^643469280 is an apocalyptic number.

643469280 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

643469280 is an abundant number, since it is smaller than the sum of its proper divisors (1383460464).

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

643469280 is a wasteful number, since it uses less digits than its factorization.

643469280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1340579 (or 1340571 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 42.

The square root of 643469280 is about 25366.6962768115. The cubic root of 643469280 is about 863.3282243883.

The spelling of 643469280 in words is "six hundred forty-three million, four hundred sixty-nine thousand, two hundred eighty".